diff --git a/createrepo.bash b/createrepo.bash
index 54ac8b2..f5a8bb7 100644
--- a/createrepo.bash
+++ b/createrepo.bash
@@ -1,11 +1,17 @@
 # bash completion for createrepo and friends
 
+_cr_compress_type()
+{
+    COMPREPLY=( $( compgen -W "$( ${1:-createrepo} --compress-type=FOO / 2>&1 \
+        | sed -ne 's/,/ /g' -ne 's/.*[Cc]ompression.*://p' )" -- "$2" ) )
+}
+
 _cr_createrepo()
 {
     COMPREPLY=()
 
     case $3 in
-        --version|-h|--help|-u|--baseurl|--distro|--content|--repo|--workers|\
+        --version|-h|--help|-u|--baseurl|--distro|--content|--repo|\
         --revision|-x|--excludes|--changelog-limit|--max-delta-rpm-size)
             return 0
             ;;
@@ -30,10 +36,24 @@ _cr_createrepo()
             COMPREPLY=( $( compgen -f -o plusdirs -X '!*.rpm' -- "$2" ) )
             return 0
             ;;
+        --retain-old-md)
+            COMPREPLY=( $( compgen -W '0 1 2 3 4 5 6 7 8 9' -- "$2" ) )
+            return 0
+            ;;
         --num-deltas)
             COMPREPLY=( $( compgen -W '1 2 3 4 5 6 7 8 9' -- "$2" ) )
             return 0
             ;;
+        --workers)
+            local min=2 max=$( getconf _NPROCESSORS_ONLN 2>/dev/null )
+            [[ -z $max || $max -lt $min ]] && max=$min
+            COMPREPLY=( $( compgen -W "{1..$max}" -- "$2" ) )
+            return 0
+            ;;
+        --compress-type)
+            _cr_compress_type "$1" "$2"
+            return 0
+            ;;
     esac
 
     if [[ $2 == -* ]] ; then
@@ -42,9 +62,9 @@ _cr_createrepo()
             --cachedir --checkts --no-database --update --update-md-path
             --skip-stat --split --pkglist --includepkg --outputdir
             --skip-symlinks --changelog-limit --unique-md-filenames
-            --simple-md-filenames --distro --content --repo --revision --deltas
-            --oldpackagedirs --num-deltas --read-pkgs-list
-            --max-delta-rpm-size --workers' -- "$2" ) )
+            --simple-md-filenames --retain-old-md --distro --content --repo
+            --revision --deltas --oldpackagedirs --num-deltas --read-pkgs-list
+            --max-delta-rpm-size --workers --compress-type' -- "$2" ) )
     else
         COMPREPLY=( $( compgen -d -- "$2" ) )
     fi
@@ -63,10 +83,14 @@ _cr_mergerepo()
             COMPREPLY=( $( compgen -d -- "$2" ) )
             return 0
             ;;
+        --compress-type)
+            _cr_compress_type "" "$2"
+            return 0
+            ;;
     esac
 
     COMPREPLY=( $( compgen -W '--version --help --repo --archlist --no-database
-        --outputdir --nogroups --noupdateinfo' -- "$2" ) )
+        --outputdir --nogroups --noupdateinfo --compress-type' -- "$2" ) )
 } &&
 complete -F _cr_mergerepo -o filenames mergerepo mergerepo.py
 
@@ -78,17 +102,22 @@ _cr_modifyrepo()
         --version|-h|--help|--mdtype)
             return 0
             ;;
+        --compress-type)
+            _cr_compress_type "" "$2"
+            return 0
+            ;;
     esac
 
     if [[ $2 == -* ]] ; then
-        COMPREPLY=( $( compgen -W '--version --help --mdtype' -- "$2" ) )
+        COMPREPLY=( $( compgen -W '--version --help --mdtype --remove
+            --compress --compress-type' -- "$2" ) )
         return 0
     fi
 
     local i argnum=1
     for (( i=1; i < ${#COMP_WORDS[@]}-1; i++ )) ; do
         if [[ ${COMP_WORDS[i]} != -* &&
-                    ${COMP_WORDS[i-1]} != @(=|--mdtype) ]]; then
+              ${COMP_WORDS[i-1]} != @(=|--@(md|compress-)type) ]]; then
             argnum=$(( argnum+1 ))
         fi
     done
diff --git a/createrepo.spec b/createrepo.spec
index 1e491cd..eea7092 100644
--- a/createrepo.spec
+++ b/createrepo.spec
@@ -11,7 +11,7 @@ URL: http://createrepo.baseurl.org/
 BuildRoot: %{_tmppath}/%{name}-%{version}root
 BuildArchitectures: noarch
 Requires: python >= 2.1, rpm-python, rpm >= 0:4.1.1, libxml2-python
-Requires: yum-metadata-parser, yum >= 3.2.29, python-deltarpm
+Requires: yum-metadata-parser, yum >= 3.2.29, python-deltarpm, pyliblzma
 
 %description
 This utility will generate a common metadata repository from a directory of
@@ -43,6 +43,9 @@ make DESTDIR=$RPM_BUILD_ROOT sysconfdir=%{_sysconfdir} install
 %{python_sitelib}/createrepo
 
 %changelog
+* Fri Sep  9 2011 Seth Vidal <skvidal at fedoraproject.org>
+- add lzma dep
+
 * Wed Jan 26 2011 Seth Vidal <skvidal at fedoraproject.org>
 - bump to 0.9.9
 - add worker.py
diff --git a/createrepo/__init__.py b/createrepo/__init__.py
index 8f2538e..1b18a9f 100644
--- a/createrepo/__init__.py
+++ b/createrepo/__init__.py
@@ -26,15 +26,16 @@ import tempfile
 import stat
 import fcntl
 import subprocess
+from select import select
 
-from yum import misc, Errors, to_unicode
-from yum.repoMDObject import RepoMD, RepoMDError, RepoData
+from yum import misc, Errors
+from yum.repoMDObject import RepoMD, RepoData
 from yum.sqlutils import executeSQL
 from yum.packageSack import MetaSack
-from yum.packages import YumAvailablePackage, YumLocalPackage
+from yum.packages import YumAvailablePackage
 
 import rpmUtils.transaction
-from utils import _, errorprint, MDError
+from utils import _, errorprint, MDError, lzma, _available_compression
 import readMetadata
 try:
     import sqlite3 as sqlite
@@ -46,8 +47,9 @@ try:
 except ImportError:
     pass
 
-from utils import _gzipOpen, bzipFile, checkAndMakeDir, GzipFile, \
+from utils import _gzipOpen, compressFile, compressOpen, checkAndMakeDir, GzipFile, \
                   checksum_and_rename, split_list_into_equal_chunks
+from utils import num_cpus_online
 import deltarpms
 
 __version__ = '0.9.9'
@@ -74,7 +76,7 @@ class MetaDataConfig(object):
         self.deltadir = None
         self.delta_relative = 'drpms/'
         self.oldpackage_paths = [] # where to look for the old packages -
-        self.deltafile = 'prestodelta.xml.gz'
+        self.deltafile = 'prestodelta.xml'
         self.num_deltas = 1 # number of older versions to delta (max)
         self.max_delta_rpm_size = 100000000
         self.update_md_path = None
@@ -86,9 +88,9 @@ class MetaDataConfig(object):
         self.skip_symlinks = False
         self.pkglist = []
         self.database_only = False
-        self.primaryfile = 'primary.xml.gz'
-        self.filelistsfile = 'filelists.xml.gz'
-        self.otherfile = 'other.xml.gz'
+        self.primaryfile = 'primary.xml'
+        self.filelistsfile = 'filelists.xml'
+        self.otherfile = 'other.xml'
         self.repomdfile = 'repomd.xml'
         self.tempdir = '.repodata'
         self.finaldir = 'repodata'
@@ -108,8 +110,10 @@ class MetaDataConfig(object):
         self.collapse_glibc_requires = True
         self.workers = 1 # number of workers to fork off to grab metadata from the pkgs
         self.worker_cmd = '/usr/share/createrepo/worker.py'
-        
         #self.worker_cmd = './worker.py' # helpful when testing
+        self.retain_old_md = 0
+        self.compress_type = 'compat'
+
         
 class SimpleMDCallBack(object):
     def errorlog(self, thing):
@@ -141,10 +145,23 @@ class MetaDataGenerator:
         self.files = []
         self.rpmlib_reqs = {}
         self.read_pkgs = []
+        self.compat_compress = False
 
         if not self.conf.directory and not self.conf.directories:
             raise MDError, "No directory given on which to run."
-
+        
+        if self.conf.compress_type == 'compat':
+            self.compat_compress = True
+            self.conf.compress_type = None
+            
+        if not self.conf.compress_type:
+            self.conf.compress_type = 'gz'
+        
+        if self.conf.compress_type not in utils._available_compression:
+            raise MDError, "Compression %s not available: Please choose from: %s" \
+                 % (self.conf.compress_type, ', '.join(utils._available_compression))
+            
+            
         if not self.conf.directories: # just makes things easier later
             self.conf.directories = [self.conf.directory]
         if not self.conf.directory: # ensure we have both in the config object
@@ -290,14 +307,13 @@ class MetaDataGenerator:
 
         def extension_visitor(filelist, dirname, names):
             for fn in names:
+                fn = os.path.join(dirname, fn)
                 if os.path.isdir(fn):
                     continue
                 if self.conf.skip_symlinks and os.path.islink(fn):
                     continue
                 elif fn[-extlen:].lower() == '%s' % (ext):
-                    relativepath = dirname.replace(startdir, "", 1)
-                    relativepath = relativepath.lstrip("/")
-                    filelist.append(os.path.join(relativepath, fn))
+                    filelist.append(fn[len(startdir):])
 
         filelist = []
         startdir = directory + '/'
@@ -311,7 +327,7 @@ class MetaDataGenerator:
     def checkTimeStamps(self):
         """check the timestamp of our target dir. If it is not newer than
            the repodata return False, else True"""
-        if self.conf.checkts:
+        if self.conf.checkts and self.conf.mdtimestamp:
             dn = os.path.join(self.conf.basedir, self.conf.directory)
             files = self.getFileList(dn, '.rpm')
             files = self.trimRpms(files)
@@ -410,9 +426,11 @@ class MetaDataGenerator:
 
     def _setupPrimary(self):
         # setup the primary metadata file
+        # FIXME - make this be  conf.compress_type once y-m-p is fixed
+        fpz = self.conf.primaryfile + '.' + 'gz'
         primaryfilepath = os.path.join(self.conf.outputdir, self.conf.tempdir,
-                                       self.conf.primaryfile)
-        fo = _gzipOpen(primaryfilepath, 'w')
+                                       fpz)
+        fo = compressOpen(primaryfilepath, 'w', 'gz')
         fo.write('<?xml version="1.0" encoding="UTF-8"?>\n')
         fo.write('<metadata xmlns="http://linux.duke.edu/metadata/common"' \
             ' xmlns:rpm="http://linux.duke.edu/metadata/rpm" packages="%s">' %
@@ -421,9 +439,11 @@ class MetaDataGenerator:
 
     def _setupFilelists(self):
         # setup the filelist file
+        # FIXME - make this be  conf.compress_type once y-m-p is fixed        
+        fpz = self.conf.filelistsfile + '.' + 'gz'
         filelistpath = os.path.join(self.conf.outputdir, self.conf.tempdir,
-                                    self.conf.filelistsfile)
-        fo = _gzipOpen(filelistpath, 'w')
+                                    fpz)
+        fo = compressOpen(filelistpath, 'w', 'gz')
         fo.write('<?xml version="1.0" encoding="UTF-8"?>\n')
         fo.write('<filelists xmlns="http://linux.duke.edu/metadata/filelists"' \
                  ' packages="%s">' % self.pkgcount)
@@ -431,9 +451,11 @@ class MetaDataGenerator:
 
     def _setupOther(self):
         # setup the other file
+        # FIXME - make this be  conf.compress_type once y-m-p is fixed        
+        fpz = self.conf.otherfile + '.' + 'gz'
         otherfilepath = os.path.join(self.conf.outputdir, self.conf.tempdir,
-                                     self.conf.otherfile)
-        fo = _gzipOpen(otherfilepath, 'w')
+                                     fpz)
+        fo = compressOpen(otherfilepath, 'w', 'gz')
         fo.write('<?xml version="1.0" encoding="UTF-8"?>\n')
         fo.write('<otherdata xmlns="http://linux.duke.edu/metadata/other"' \
                  ' packages="%s">' %
@@ -442,9 +464,10 @@ class MetaDataGenerator:
 
     def _setupDelta(self):
         # setup the other file
+        fpz = self.conf.deltafile + '.' + self.conf.compress_type        
         deltafilepath = os.path.join(self.conf.outputdir, self.conf.tempdir,
-                                     self.conf.deltafile)
-        fo = _gzipOpen(deltafilepath, 'w')
+                                     fpz)
+        fo = compressOpen(deltafilepath, 'w', self.conf.compress_type)
         fo.write('<?xml version="1.0" encoding="UTF-8"?>\n')
         fo.write('<prestodelta>\n')
         return fo
@@ -520,6 +543,7 @@ class MetaDataGenerator:
         # go on their merry way
         
         newpkgs = []
+        keptpkgs = []
         if self.conf.update:
             # if we're in --update mode then only act on the new/changed pkgs
             for pkg in pkglist:
@@ -530,39 +554,13 @@ class MetaDataGenerator:
                 old_pkg = pkg
                 if pkg.find("://") != -1:
                     old_pkg = os.path.basename(pkg)
-                nodes = self.oldData.getNodes(old_pkg)
-                if nodes is not None: # we have a match in the old metadata
+                old_po = self.oldData.getNodes(old_pkg)
+                if old_po: # we have a match in the old metadata
                     if self.conf.verbose:
                         self.callback.log(_("Using data from old metadata for %s")
                                             % pkg)
-                    (primarynode, filenode, othernode) = nodes
-
-                    for node, outfile in ((primarynode, self.primaryfile),
-                                          (filenode, self.flfile),
-                                          (othernode, self.otherfile)):
-                        if node is None:
-                            break
-
-                        if self.conf.baseurl:
-                            anode = node.children
-                            while anode is not None:
-                                if anode.type != "element":
-                                    anode = anode.next
-                                    continue
-                                if anode.name == "location":
-                                    anode.setProp('xml:base', self.conf.baseurl)
-                                anode = anode.next
-
-                        output = node.serialize('UTF-8', self.conf.pretty)
-                        if output:
-                            outfile.write(output)
-                        else:
-                            if self.conf.verbose:
-                                self.callback.log(_("empty serialize on write to" \
-                                                    "%s in %s") % (outfile, pkg))
-                        outfile.write('\n')
-
-                    self.oldData.freeNodes(pkg)
+                    keptpkgs.append((pkg, old_po))
+
                     #FIXME - if we're in update and we have deltas enabled
                     # check the presto data for this pkg and write its info back out
                     # to our deltafile
@@ -584,32 +582,45 @@ class MetaDataGenerator:
             po = None
             if isinstance(pkg, YumAvailablePackage):
                 po = pkg
-                self.read_pkgs.append(po.localpath)
+                self.read_pkgs.append(po.localPkg())
 
             # if we're dealing with remote pkgs - pitch it over to doing
             # them one at a time, for now. 
             elif pkg.find('://') != -1:
-                po = self.read_in_package(pkgfile, pkgpath=pkgpath, reldir=reldir)
+                po = self.read_in_package(pkg, pkgpath=pkgpath, reldir=reldir)
                 self.read_pkgs.append(pkg)
             
             if po:
-                self.primaryfile.write(po.xml_dump_primary_metadata())
-                self.flfile.write(po.xml_dump_filelists_metadata())
-                self.otherfile.write(po.xml_dump_other_metadata(
-                                     clog_limit=self.conf.changelog_limit))
+                keptpkgs.append((pkg, po))
                 continue
                 
             pkgfiles.append(pkg)
-            
-       
+
+        keptpkgs.sort(reverse=True)
+        # keptkgs is a list of (filename, po), pkgfiles is a list if filenames.
+        # Need to write them in sorted(filename) order.  We loop over pkgfiles,
+        # inserting keptpkgs in right spots (using the upto argument).
+        def save_keptpkgs(upto):
+            while keptpkgs and (upto is None or keptpkgs[-1][0] < upto):
+                filename, po = keptpkgs.pop()
+                # reset baseurl in the old pkg
+                po.basepath = self.conf.baseurl
+                self.primaryfile.write(po.xml_dump_primary_metadata())
+                self.flfile.write(po.xml_dump_filelists_metadata())
+                self.otherfile.write(po.xml_dump_other_metadata(
+                    clog_limit=self.conf.changelog_limit))
+
         if pkgfiles:
             # divide that list by the number of workers and fork off that many
             # workers to tmpdirs
             # waitfor the workers to finish and as each one comes in
             # open the files they created and write them out to our metadata
             # add up the total pkg counts and return that value
-            worker_tmp_path = tempfile.mkdtemp()
-            worker_chunks = utils.split_list_into_equal_chunks(pkgfiles,  self.conf.workers)
+            self._worker_tmp_path = tempfile.mkdtemp() # setting this in the base object so we can clean it up later
+            if self.conf.workers < 1:
+                self.conf.workers = num_cpus_online()
+            pkgfiles.sort()
+            worker_chunks = split_list_into_equal_chunks(pkgfiles, self.conf.workers)
             worker_cmd_dict = {}
             worker_jobs = {}
             base_worker_cmdline = [self.conf.worker_cmd, 
@@ -617,7 +628,8 @@ class MetaDataGenerator:
                     '--pkgoptions=_collapse_libc_requires=%s' % self.conf.collapse_glibc_requires, 
                     '--pkgoptions=_cachedir=%s' % self.conf.cachedir,
                     '--pkgoptions=_baseurl=%s' % self.conf.baseurl,
-                    '--globalopts=clog_limit=%s' % self.conf.changelog_limit,]
+                    '--globalopts=clog_limit=%s' % self.conf.changelog_limit,
+                    '--globalopts=sumtype=%s' % self.conf.sumtype, ]
             
             if self.conf.quiet:
                 base_worker_cmdline.append('--quiet')
@@ -626,15 +638,14 @@ class MetaDataGenerator:
                 base_worker_cmdline.append('--verbose')
                 
             for worker_num in range(self.conf.workers):
-                # make the worker directory
+                pkl = self._worker_tmp_path + '/pkglist-%s' % worker_num
+                f = open(pkl, 'w') 
+                f.write('\n'.join(worker_chunks[worker_num]))
+                f.close()
+                
                 workercmdline = []
                 workercmdline.extend(base_worker_cmdline)
-                thisdir = worker_tmp_path + '/' + str(worker_num)
-                if checkAndMakeDir(thisdir):
-                    workercmdline.append('--tmpmdpath=%s' % thisdir)
-                else:
-                    raise MDError, "Unable to create worker path: %s" % thisdir
-                workercmdline.extend(worker_chunks[worker_num])
+                workercmdline.append('--pkglist=%s/pkglist-%s' % (self._worker_tmp_path, worker_num))
                 worker_cmd_dict[worker_num] = workercmdline
             
                 
@@ -647,49 +658,60 @@ class MetaDataGenerator:
                                         stderr=subprocess.PIPE)
                 worker_jobs[num] = job
             
-            gimmebreak = 0
-            while gimmebreak != len(worker_jobs.keys()):
-                gimmebreak = 0
-                for (num,job) in worker_jobs.items():
-                    if job.poll() is not None:
-                        gimmebreak+=1
-                    line = job.stdout.readline()
-                    if line:
+            files = self.primaryfile, self.flfile, self.otherfile
+            def log_messages(num):
+                job = worker_jobs[num]
+                while True:
+                    # check stdout and stderr
+                    for stream in select((job.stdout, job.stderr), (), ())[0]:
+                        line = stream.readline()
+                        if line: break
+                    else:
+                        return # EOF, EOF
+                    if stream is job.stdout:
+                        if line.startswith('*** '):
+                            # get data, save to local files
+                            for out, size in zip(files, line[4:].split()):
+                                out.write(stream.read(int(size)))
+                            return
                         self.callback.log('Worker %s: %s' % (num, line.rstrip()))
-                    line = job.stderr.readline()
-                    if line:
+                    else:
                         self.callback.errorlog('Worker %s: %s' % (num, line.rstrip()))
+
+            for i, pkg in enumerate(pkgfiles):
+                # insert cached packages
+                save_keptpkgs(pkg)
+
+                # save output to local files
+                log_messages(i % self.conf.workers)
+
+            for (num, job) in worker_jobs.items():
+                # process remaining messages on stderr
+                log_messages(num)
+
+                if job.wait() != 0:
+                    msg = "Worker exited with non-zero value: %s. Fatal." % job.returncode
+                    self.callback.errorlog(msg)
+                    raise MDError, msg
                     
-                
             if not self.conf.quiet:
                 self.callback.log("Workers Finished")
-            # finished with workers
-            # go to their dirs and add the contents
-            if not self.conf.quiet:
-                self.callback.log("Gathering worker results")
-            for num in range(self.conf.workers):
-                for (fn, fo) in (('primary.xml', self.primaryfile), 
-                           ('filelists.xml', self.flfile),
-                           ('other.xml', self.otherfile)):
-                    fnpath = worker_tmp_path + '/' + str(num) + '/' + fn
-                    if os.path.exists(fnpath):
-                        fo.write(open(fnpath, 'r').read())
-
                     
             for pkgfile in pkgfiles:
                 if self.conf.deltas:
-                    po = self.read_in_package(pkgfile, pkgpath=pkgpath, reldir=reldir)
-                    self._do_delta_rpm_package(po)
+                    try:
+                        po = self.read_in_package(pkgfile, pkgpath=pkgpath, reldir=reldir)
+                        self._do_delta_rpm_package(po)
+                    except MDError, e:
+                        errorprint(e)
+                        continue
                 self.read_pkgs.append(pkgfile)
 
+        save_keptpkgs(None) # append anything left
         return self.current_pkg
 
 
     def closeMetadataDocs(self):
-        if not self.conf.quiet:
-            self.callback.log('')
-
-
         # save them up to the tmp locations:
         if not self.conf.quiet:
             self.callback.log(_('Saving Primary metadata'))
@@ -784,7 +806,6 @@ class MetaDataGenerator:
             return self._old_package_dict
 
         self._old_package_dict = {}
-        opl = []
         for d in self.conf.oldpackage_paths:
             for f in self.getFileList(d, '.rpm'):
                 fp = d + '/' + f
@@ -833,7 +854,7 @@ class MetaDataGenerator:
         return ' '.join(results)
 
     def _createRepoDataObject(self, mdfile, mdtype, compress=True, 
-                              compress_type='gzip', attribs={}):
+                              compress_type=None, attribs={}):
         """return random metadata as RepoData object to be  added to RepoMD
            mdfile = complete path to file
            mdtype = the metadata type to use
@@ -843,15 +864,13 @@ class MetaDataGenerator:
         sfile = os.path.basename(mdfile)
         fo = open(mdfile, 'r')
         outdir = os.path.join(self.conf.outputdir, self.conf.tempdir)
+        if not compress_type:
+            compress_type = self.conf.compress_type
         if compress:
-            if compress_type == 'gzip':
-                sfile = '%s.gz' % sfile
-                outfn = os.path.join(outdir, sfile)
-                output = GzipFile(filename = outfn, mode='wb')
-            elif compress_type == 'bzip2':
-                sfile = '%s.bz2' % sfile
-                outfn = os.path.join(outdir, sfile)
-                output = BZ2File(filename = outfn, mode='wb')
+            sfile = '%s.%s' % (sfile, compress_type)
+            outfn = os.path.join(outdir, sfile)
+            output = compressOpen(outfn, mode='wb', compress_type=compress_type)
+                
         else:
             outfn  = os.path.join(outdir, sfile)
             output = open(outfn, 'w')
@@ -874,14 +893,13 @@ class MetaDataGenerator:
 
         thisdata = RepoData()
         thisdata.type = mdtype
-        baseloc = None
         thisdata.location = (self.conf.baseurl, os.path.join(self.conf.finaldir, sfile))
         thisdata.checksum = (self.conf.sumtype, csum)
         if compress:
             thisdata.openchecksum  = (self.conf.sumtype, open_csum)
         
         thisdata.size = str(os.stat(outfn).st_size)
-        thisdata.timestamp = str(os.stat(outfn).st_mtime)
+        thisdata.timestamp = str(int(os.stat(outfn).st_mtime))
         for (k, v) in attribs.items():
             setattr(thisdata, k, str(v))
         
@@ -925,9 +943,14 @@ class MetaDataGenerator:
             rp = sqlitecachec.RepodataParserSqlite(repopath, repomd.repoid, None)
 
         for (rpm_file, ftype) in workfiles:
+            # when we fix y-m-p and non-gzipped xml files - then we can make this just add
+            # self.conf.compress_type
+            if ftype in ('other', 'filelists', 'primary'):
+                rpm_file = rpm_file + '.' + 'gz'
+            elif rpm_file.find('.') != -1 and rpm_file.split('.')[-1] not in _available_compression:
+                rpm_file = rpm_file + '.' + self.conf.compress_type
             complete_path = os.path.join(repopath, rpm_file)
-
-            zfo = _gzipOpen(complete_path)
+            zfo = compressOpen(complete_path)
             # This is misc.checksum() done locally so we can get the size too.
             data = misc.Checksums([sumtype])
             while data.read(zfo, 2**16):
@@ -966,14 +989,20 @@ class MetaDataGenerator:
                     good_name = '%s.sqlite' % ftype
                     resultpath = os.path.join(repopath, good_name)
 
+                    # compat compression for rhel5 compatibility from fedora :(
+                    compress_type = self.conf.compress_type
+                    if self.compat_compress:
+                        compress_type = 'bz2'
+                        
                     # rename from silly name to not silly name
                     os.rename(tmp_result_path, resultpath)
-                    compressed_name = '%s.bz2' % good_name
+                    compressed_name = '%s.%s' % (good_name, compress_type)
                     result_compressed = os.path.join(repopath, compressed_name)
                     db_csums[ftype] = misc.checksum(sumtype, resultpath)
 
                     # compress the files
-                    bzipFile(resultpath, result_compressed)
+
+                    compressFile(resultpath, result_compressed, compress_type)
                     # csum the compressed file
                     db_compressed_sums[ftype] = misc.checksum(sumtype,
                                                              result_compressed)
@@ -983,8 +1012,8 @@ class MetaDataGenerator:
                     os.unlink(resultpath)
 
                     if self.conf.unique_md_filenames:
-                        csum_compressed_name = '%s-%s.bz2' % (
-                                           db_compressed_sums[ftype], good_name)
+                        csum_compressed_name = '%s-%s.%s' % (
+                                           db_compressed_sums[ftype], good_name, compress_type)
                         csum_result_compressed =  os.path.join(repopath,
                                                            csum_compressed_name)
                         os.rename(result_compressed, csum_result_compressed)
@@ -1001,7 +1030,7 @@ class MetaDataGenerator:
                     data.location = (self.conf.baseurl, 
                               os.path.join(self.conf.finaldir, compressed_name))
                     data.checksum = (sumtype, db_compressed_sums[ftype])
-                    data.timestamp = str(db_stat.st_mtime)
+                    data.timestamp = str(int(db_stat.st_mtime))
                     data.size = str(db_stat.st_size)
                     data.opensize = str(un_stat.st_size)
                     data.openchecksum = (sumtype, db_csums[ftype])
@@ -1020,7 +1049,13 @@ class MetaDataGenerator:
             data.openchecksum = (sumtype, uncsum)
 
             if self.conf.unique_md_filenames:
-                res_file = '%s-%s.xml.gz' % (csum, ftype)
+                if ftype in ('primary', 'filelists', 'other'):
+                    compress = 'gz'
+                else:
+                    compress = self.conf.compress_type
+                
+                main_name = '.'.join(rpm_file.split('.')[:-1])
+                res_file = '%s-%s.%s' % (csum, main_name, compress)
                 orig_file = os.path.join(repopath, rpm_file)
                 dest_file = os.path.join(repopath, res_file)
                 os.rename(orig_file, dest_file)
@@ -1046,7 +1081,7 @@ class MetaDataGenerator:
             
 
         if self.conf.additional_metadata:
-            for md_type, mdfile in self.conf.additional_metadata.items():
+            for md_type, md_file in self.conf.additional_metadata.items():
                 mdcontent = self._createRepoDataObject(md_file, md_type)
                 repomd.repoData[mdcontent.type] = mdcontent
                 
@@ -1110,23 +1145,43 @@ class MetaDataGenerator:
                     raise MDError, _(
                     'Could not remove old metadata file: %s: %s') % (oldfile, e)
 
-        # Move everything else back from olddir (eg. repoview files)
-        try:
-            old_contents = os.listdir(output_old_dir)
-        except (OSError, IOError), e:
-            old_contents = []
-            
+        old_to_remove = []
+        old_pr = []
+        old_fl = []
+        old_ot = []
+        old_pr_db = []
+        old_fl_db = []
+        old_ot_db = []
         for f in os.listdir(output_old_dir):
             oldfile = os.path.join(output_old_dir, f)
             finalfile = os.path.join(output_final_dir, f)
-            if f.find('-') != -1 and f.split('-')[1] in ('primary.sqlite.bz2',
-                    'filelists.sqlite.bz2', 'primary.xml.gz','other.sqlite.bz2',
-                    'other.xml.gz','filelists.xml.gz'):
-                os.remove(oldfile) # kill off the old ones
-                continue
-            if f in ('filelists.sqlite.bz2', 'other.sqlite.bz2',
-                     'primary.sqlite.bz2'):
-                os.remove(oldfile)
+
+            for (end,lst) in (('-primary.sqlite', old_pr_db), ('-primary.xml', old_pr),
+                           ('-filelists.sqlite', old_fl_db), ('-filelists.xml', old_fl),
+                           ('-other.sqlite', old_ot_db), ('-other.xml', old_ot)):
+                fn = '.'.join(f.split('.')[:-1])
+                if fn.endswith(end):
+                    lst.append(oldfile)
+                    break
+
+        # make a list of the old metadata files we don't want to remove.
+        for lst in (old_pr, old_fl, old_ot, old_pr_db, old_fl_db, old_ot_db):
+            sortlst = sorted(lst, key=lambda x: os.path.getmtime(x),
+                             reverse=True)
+            for thisf in sortlst[self.conf.retain_old_md:]:
+                old_to_remove.append(thisf)
+
+        for f in os.listdir(output_old_dir):
+            oldfile = os.path.join(output_old_dir, f)
+            finalfile = os.path.join(output_final_dir, f)
+            fn = '.'.join(f.split('.')[:-1])
+            if fn in ('filelists.sqlite', 'other.sqlite',
+                     'primary.sqlite') or oldfile in old_to_remove:
+                try:
+                    os.remove(oldfile)
+                except (OSError, IOError), e:
+                    raise MDError, _(
+                    'Could not remove old metadata file: %s: %s') % (oldfile, e)
                 continue
 
             if os.path.exists(finalfile):
@@ -1147,14 +1202,19 @@ class MetaDataGenerator:
                     msg += _('Error was %s') % e
                     raise MDError, msg
 
-        try:
-            os.rmdir(output_old_dir)
-        except OSError, e:
-            self.errorlog(_('Could not remove old metadata dir: %s')
-                          % self.conf.olddir)
-            self.errorlog(_('Error was %s') % e)
-            self.errorlog(_('Please clean up this directory manually.'))
+        self._cleanup_tmp_repodata_dir()
+        self._cleanup_update_tmp_dir()        
+        self._write_out_read_pkgs_list()
+
 
+    def _cleanup_update_tmp_dir(self):
+        if not self.conf.update:
+            return
+        
+        shutil.rmtree(self.oldData._repo.basecachedir, ignore_errors=True)
+        shutil.rmtree(self.oldData._repo.base_persistdir, ignore_errors=True)
+        
+    def _write_out_read_pkgs_list(self):
         # write out the read_pkgs_list file with self.read_pkgs
         if self.conf.read_pkgs_list:
             try:
@@ -1167,6 +1227,23 @@ class MetaDataGenerator:
                               % self.conf.read_pkgs_list)
                 self.errorlog(_('Error was %s') % e)
 
+    def _cleanup_tmp_repodata_dir(self):
+        output_old_dir = os.path.join(self.conf.outputdir, self.conf.olddir)
+        output_temp_dir = os.path.join(self.conf.outputdir, self.conf.tempdir)
+        for dirbase in (self.conf.olddir, self.conf.tempdir):
+            dirpath = os.path.join(self.conf.outputdir, dirbase)
+            if os.path.exists(dirpath):
+                try:
+                    os.rmdir(dirpath)
+                except OSError, e:
+                    self.errorlog(_('Could not remove  temp metadata dir: %s')
+                                  % dirbase)
+                    self.errorlog(_('Error was %s') % e)
+                    self.errorlog(_('Please clean up this directory manually.'))
+        # our worker tmp path
+        if hasattr(self, '_worker_tmp_path') and os.path.exists(self._worker_tmp_path):
+            shutil.rmtree(self._worker_tmp_path, ignore_errors=True)
+        
     def setup_sqlite_dbs(self, initdb=True):
         """sets up the sqlite dbs w/table schemas and db_infos"""
         destdir = os.path.join(self.conf.outputdir, self.conf.tempdir)
@@ -1194,24 +1271,6 @@ class SplitMetaDataGenerator(MetaDataGenerator):
         (scheme, netloc, path, query, fragid) = urlparse.urlsplit(url)
         return urlparse.urlunsplit((scheme, netloc, path, query, str(fragment)))
 
-    def getFileList(self, directory, ext):
-
-        extlen = len(ext)
-
-        def extension_visitor(arg, dirname, names):
-            for fn in names:
-                if os.path.isdir(fn):
-                    continue
-                elif fn[-extlen:].lower() == '%s' % (ext):
-                    reldir = os.path.basename(dirname)
-                    if reldir == os.path.basename(directory):
-                        reldir = ""
-                    arg.append(os.path.join(reldir, fn))
-
-        rpmlist = []
-        os.path.walk(directory, extension_visitor, rpmlist)
-        return rpmlist
-
     def doPkgMetadata(self):
         """all the heavy lifting for the package metadata"""
         if len(self.conf.directories) == 1:
@@ -1232,6 +1291,19 @@ class SplitMetaDataGenerator(MetaDataGenerator):
                     thisdir = os.path.join(self.conf.basedir, mydir)
 
             filematrix[mydir] = self.getFileList(thisdir, '.rpm')
+
+            #  pkglist is a bit different for split media, as we have to know
+            # which dir. it belongs to. So we walk the dir. and then filter.
+            # We could be faster by not walking the dir. ... but meh.
+            if self.conf.pkglist:
+                pkglist = set(self.conf.pkglist)
+                pkgs = []
+                for fname in filematrix[mydir]:
+                    if fname not in pkglist:
+                        continue
+                    pkgs.append(fname)
+                filematrix[mydir] = pkgs
+
             self.trimRpms(filematrix[mydir])
             self.pkgcount += len(filematrix[mydir])
 
@@ -1240,7 +1312,6 @@ class SplitMetaDataGenerator(MetaDataGenerator):
         self.conf.baseurl = self._getFragmentUrl(self.conf.baseurl, mediano)
         try:
             self.openMetadataDocs()
-            original_basedir = self.conf.basedir
             for mydir in self.conf.directories:
                 self.conf.baseurl = self._getFragmentUrl(self.conf.baseurl, mediano)
                 self.writeMetadataDocs(filematrix[mydir], mydir)
diff --git a/createrepo/merge.py b/createrepo/merge.py
index b3b2ea1..1ac43bb 100644
--- a/createrepo/merge.py
+++ b/createrepo/merge.py
@@ -24,6 +24,7 @@ from yum.misc import unique, getCacheDir
 import yum.update_md
 import rpmUtils.arch
 import operator
+from utils import MDError
 import createrepo
 import tempfile
 
@@ -84,6 +85,8 @@ class RepoMergeBase:
         # in the repolist
         count = 0
         for r in self.repolist:
+            if r[0] == '/':
+                r = 'file://' + r # just fix the file repos, this is silly.
             count +=1
             rid = 'repo%s' % count
             n = self.yumbase.add_enable_repo(rid, baseurls=[r],
@@ -92,7 +95,10 @@ class RepoMergeBase:
             n._merge_rank = count
 
         #setup our sacks
-        self.yumbase._getSacks(archlist=self.archlist)
+        try:
+            self.yumbase._getSacks(archlist=self.archlist)
+        except yum.Errors.RepoError, e:
+            raise MDError, "Could not setup merge repo pkgsack: %s" % e
 
         myrepos = self.yumbase.repos.listEnabled()
 
@@ -102,11 +108,16 @@ class RepoMergeBase:
     def write_metadata(self, outputdir=None):
         mytempdir = tempfile.mkdtemp()
         if self.groups:
-            comps_fn = mytempdir + '/groups.xml'
-            compsfile = open(comps_fn, 'w')
-            compsfile.write(self.yumbase.comps.xml())
-            compsfile.close()
-            self.mdconf.groupfile=comps_fn
+            try:
+                comps_fn = mytempdir + '/groups.xml'
+                compsfile = open(comps_fn, 'w')
+                compsfile.write(self.yumbase.comps.xml())
+                compsfile.close()
+            except yum.Errors.GroupsError, e:
+                # groups not being available shouldn't be a fatal error
+                pass
+            else:
+                self.mdconf.groupfile=comps_fn
 
         if self.updateinfo:
             ui_fn = mytempdir + '/updateinfo.xml'
diff --git a/createrepo/readMetadata.py b/createrepo/readMetadata.py
index 27d3690..54863cb 100644
--- a/createrepo/readMetadata.py
+++ b/createrepo/readMetadata.py
@@ -16,11 +16,25 @@
 # Copyright 2006 Red Hat
 
 import os
-import libxml2
 import stat
 from utils import errorprint, _
 
-from yum import repoMDObject
+import yum
+from yum import misc
+from yum.Errors import YumBaseError
+import tempfile
+class CreaterepoPkgOld(yum.sqlitesack.YumAvailablePackageSqlite):
+    # special for special people like us.
+    def _return_remote_location(self):
+
+        if self.basepath:
+            msg = """<location xml:base="%s" href="%s"/>\n""" % (
+                                     misc.to_xml(self.basepath, attrib=True),
+                                     misc.to_xml(self.relativepath, attrib=True))
+        else:
+            msg = """<location href="%s"/>\n""" % misc.to_xml(self.relativepath, attrib=True)
+
+        return msg  
 
 
 class MetadataIndex(object):
@@ -30,178 +44,72 @@ class MetadataIndex(object):
             opts = {}
         self.opts = opts
         self.outputdir = outputdir
+        realpath = os.path.realpath(outputdir)
         repodatadir = self.outputdir + '/repodata'
-        myrepomdxml = repodatadir + '/repomd.xml'
-        if os.path.exists(myrepomdxml):
-            repomd = repoMDObject.RepoMD('garbageid', myrepomdxml)
-            b = repomd.getData('primary').location[1]
-            f = repomd.getData('filelists').location[1]
-            o = repomd.getData('other').location[1]
-            basefile = os.path.join(self.outputdir, b)
-            filelistfile = os.path.join(self.outputdir, f)
-            otherfile = os.path.join(self.outputdir, o)
-        else:
-            basefile = filelistfile = otherfile = ""
-
-        self.files = {'base' : basefile,
-                      'filelist' : filelistfile,
-                      'other' : otherfile}
-        self.scan()
+        self._repo = yum.yumRepo.YumRepository('garbageid')
+        self._repo.baseurl = 'file://' + realpath
+        self._repo.basecachedir = tempfile.mkdtemp(dir='/var/tmp', prefix="createrepo")
+        self._repo.base_persistdir = tempfile.mkdtemp(dir='/var/tmp', prefix="createrepo-p")
+        self._repo.metadata_expire = 1
+        self._repo.gpgcheck = 0
+        self._repo.repo_gpgcheck = 0
+        self._repo._sack = yum.sqlitesack.YumSqlitePackageSack(CreaterepoPkgOld)
+        self.pkg_tups_by_path = {}
+        try:
+            self.scan()
+        except YumBaseError, e:
+            print "Could not find valid repo at: %s" % self.outputdir
+        
 
     def scan(self):
-        """Read in and index old repo data"""
-        self.basenodes = {}
-        self.filesnodes = {}
-        self.othernodes = {}
-        self.pkg_ids = {}
+        """Read in old repodata"""
         if self.opts.get('verbose'):
             print _("Scanning old repo data")
-        for fn in self.files.values():
-            if not os.path.exists(fn):
-                #cannot scan
-                errorprint(_("Warning: Old repodata file missing: %s") % fn)
-                return
-        root = libxml2.parseFile(self.files['base']).getRootElement()
-        self._scanPackageNodes(root, self._handleBase)
-        if self.opts.get('verbose'):
-            print _("Indexed %i base nodes" % len(self.basenodes))
-        root = libxml2.parseFile(self.files['filelist']).getRootElement()
-        self._scanPackageNodes(root, self._handleFiles)
-        if self.opts.get('verbose'):
-            print _("Indexed %i filelist nodes" % len(self.filesnodes))
-        root = libxml2.parseFile(self.files['other']).getRootElement()
-        self._scanPackageNodes(root, self._handleOther)
-        if self.opts.get('verbose'):
-            print _("Indexed %i other nodes" % len(self.othernodes))
-        #reverse index pkg ids to track references
-        self.pkgrefs = {}
-        for relpath, pkgid in self.pkg_ids.iteritems():
-            self.pkgrefs.setdefault(pkgid,[]).append(relpath)
-
-    def _scanPackageNodes(self, root, handler):
-        node = root.children
-        while node is not None:
-            if node.type != "element":
-                node = node.next
+        self._repo.sack.populate(self._repo, 'all', None, False)
+        for thispo in self._repo.sack:
+            mtime = thispo.filetime
+            size = thispo.size
+            relpath = thispo.relativepath
+            do_stat = self.opts.get('do_stat', True)
+            if mtime is None:
+                print _("mtime missing for %s") % relpath
                 continue
-            if node.name == "package":
-                handler(node)
-            node = node.next
-
-    def _handleBase(self, node):
-        top = node
-        node = node.children
-        pkgid = None
-        mtime = None
-        size = None
-        relpath = None
-        do_stat = self.opts.get('do_stat', True)
-        while node is not None:
-            if node.type != "element":
-                node = node.next
+            if size is None:
+                print _("size missing for %s") % relpath
                 continue
-            if node.name == "checksum":
-                pkgid = node.content
-            elif node.name == "time":
-                mtime = int(node.prop('file'))
-            elif node.name == "size":
-                size = int(node.prop('package'))
-            elif node.name == "location":
-                relpath = node.prop('href')
-            node = node.next
-        if relpath is None:
-            print _("Incomplete data for node")
-            return
-        if pkgid is None:
-            print _("pkgid missing for %s") % relpath
-            return
-        if mtime is None:
-            print _("mtime missing for %s") % relpath
-            return
-        if size is None:
-            print _("size missing for %s") % relpath
-            return
-        if do_stat:
-            filepath = os.path.join(self.opts['pkgdir'], relpath)
-            try:
-                st = os.stat(filepath)
-            except OSError:
-                #file missing -- ignore
-                return
-            if not stat.S_ISREG(st.st_mode):
-                #ignore non files
-                return
-            #check size and mtime
-            if st.st_size != size:
-                if self.opts.get('verbose'):
-                    print _("Size (%i -> %i) changed for file %s") % (size,st.st_size,filepath)
-                return
-            if int(st.st_mtime) != mtime:
-                if self.opts.get('verbose'):
-                    print _("Modification time changed for %s") % filepath
-                return
-        #otherwise we index
-        self.basenodes[relpath] = top
-        self.pkg_ids[relpath] = pkgid
-
-    def _handleFiles(self, node):
-        pkgid = node.prop('pkgid')
-        if pkgid:
-            self.filesnodes[pkgid] = node
-
-    def _handleOther(self, node):
-        pkgid = node.prop('pkgid')
-        if pkgid:
-            self.othernodes[pkgid] = node
+            if do_stat:
+                filepath = os.path.join(self.opts['pkgdir'], relpath)
+                try:
+                    st = os.stat(filepath)
+                except OSError:
+                    #file missing -- ignore
+                    continue
+                if not stat.S_ISREG(st.st_mode):
+                    #ignore non files
+                    continue
+                #check size and mtime
+                if st.st_size != size:
+                    if self.opts.get('verbose'):
+                        print _("Size (%i -> %i) changed for file %s") % (size,st.st_size,filepath)
+                    continue
+                if int(st.st_mtime) != mtime:
+                    if self.opts.get('verbose'):
+                        print _("Modification time changed for %s") % filepath
+                    continue
+
+            self.pkg_tups_by_path[relpath] = thispo.pkgtup
+
 
-    def getNodes(self, relpath):
-        """Return base, filelist, and other nodes for file, if they exist
 
-        Returns a tuple of nodes, or None if not found
+    def getNodes(self, relpath):
+        """return a package object based on relative path of pkg
         """
-        bnode = self.basenodes.get(relpath,None)
-        if bnode is None:
-            return None
-        pkgid = self.pkg_ids.get(relpath,None)
-        if pkgid is None:
-            print _("No pkgid found for: %s") % relpath
-            return None
-        fnode = self.filesnodes.get(pkgid,None)
-        if fnode is None:
-            return None
-        onode = self.othernodes.get(pkgid,None)
-        if onode is None:
-            return None
-        return bnode, fnode, onode
-
-    def freeNodes(self,relpath):
-        #causing problems
-        """Free up nodes corresponding to file, if possible"""
-        bnode = self.basenodes.get(relpath,None)
-        if bnode is None:
-            print "Missing node for %s" % relpath
-            return
-        bnode.unlinkNode()
-        bnode.freeNode()
-        del self.basenodes[relpath]
-        pkgid = self.pkg_ids.get(relpath,None)
-        if pkgid is None:
-            print _("No pkgid found for: %s") % relpath
-            return None
-        del self.pkg_ids[relpath]
-        dups = self.pkgrefs.get(pkgid)
-        dups.remove(relpath)
-        if len(dups):
-            #still referenced
-            return
-        del self.pkgrefs[pkgid]
-        for nodes in self.filesnodes, self.othernodes:
-            node = nodes.get(pkgid)
-            if node is not None:
-                node.unlinkNode()
-                node.freeNode()
-                del nodes[pkgid]
+        if relpath in self.pkg_tups_by_path:
+            pkgtup = self.pkg_tups_by_path[relpath]
+            return self._repo.sack.searchPkgTuple(pkgtup)[0]
+        return None
 
+    
 
 if __name__ == "__main__":
     cwd = os.getcwd()
@@ -209,9 +117,9 @@ if __name__ == "__main__":
             'pkgdir': cwd}
 
     idx = MetadataIndex(cwd, opts)
-    for fn in idx.basenodes.keys():
-        a,b,c, = idx.getNodes(fn)
-        a.serialize()
-        b.serialize()
-        c.serialize()
-        idx.freeNodes(fn)
+    for fn in idx.pkg_tups_by_path:
+        po = idx.getNodes(fn)
+        print po.xml_dump_primary_metadata()
+        print po.xml_dump_filelists_metadata()
+        print po.xml_dump_other_metadata()
+
diff --git a/createrepo/utils.py b/createrepo/utils.py
index 995c3b9..b0d92ec 100644
--- a/createrepo/utils.py
+++ b/createrepo/utils.py
@@ -23,6 +23,12 @@ import bz2
 import gzip
 from gzip import write32u, FNAME
 from yum import misc
+_available_compression = ['gz', 'bz2']
+try:
+    import lzma
+    _available_compression.append('xz')
+except ImportError:
+    lzma = None
 
 def errorprint(stuff):
     print >> sys.stderr, stuff
@@ -34,22 +40,14 @@ def _(args):
 
 class GzipFile(gzip.GzipFile):
     def _write_gzip_header(self):
+        # Generate a header that is easily reproduced with gzip -9 -n on
+        # an unix-like system
         self.fileobj.write('\037\213')             # magic header
         self.fileobj.write('\010')                 # compression method
-        if hasattr(self, 'name'):
-            fname = self.name[:-3]
-        else:
-            fname = self.filename[:-3]
-        flags = 0
-        if fname:
-            flags = FNAME
-        self.fileobj.write(chr(flags))
-        write32u(self.fileobj, long(0))
-        self.fileobj.write('\002')
-        self.fileobj.write('\377')
-        if fname:
-            self.fileobj.write(fname + '\000')
-
+        self.fileobj.write('\000')                 # flags
+        write32u(self.fileobj, long(0))            # timestamp
+        self.fileobj.write('\002')                 # max compression
+        self.fileobj.write('\003')                 # UNIX
 
 def _gzipOpen(filename, mode="rb", compresslevel=9):
     return GzipFile(filename, mode, compresslevel)
@@ -69,6 +67,75 @@ def bzipFile(source, dest):
     s_fn.close()
 
 
+def xzFile(source, dest):
+    if not 'xz' in _available_compression:
+        raise MDError, "Cannot use xz for compression, library/module is not available"
+        
+    s_fn = open(source, 'rb')
+    destination = lzma.LZMAFile(dest, 'w')
+
+    while True:
+        data = s_fn.read(1024000)
+
+        if not data: break
+        destination.write(data)
+
+    destination.close()
+    s_fn.close()
+
+def gzFile(source, dest):
+        
+    s_fn = open(source, 'rb')
+    destination = GzipFile(dest, 'w')
+
+    while True:
+        data = s_fn.read(1024000)
+
+        if not data: break
+        destination.write(data)
+
+    destination.close()
+    s_fn.close()
+
+
+class Duck:
+    def __init__(self, **attr):
+        self.__dict__ = attr
+
+
+def compressFile(source, dest, compress_type):
+    """Compress an existing file using any compression type from source to dest"""
+    
+    if compress_type == 'xz':
+        xzFile(source, dest)
+    elif compress_type == 'bz2':
+        bzipFile(source, dest)
+    elif compress_type == 'gz':
+        gzFile(source, dest)
+    else:
+        raise MDError, "Unknown compression type %s" % compress_type
+    
+def compressOpen(fn, mode='rb', compress_type=None):
+    
+    if not compress_type:
+        # we are readonly and we don't give a compress_type - then guess based on the file extension
+        compress_type = fn.split('.')[-1]
+        if compress_type not in _available_compression:
+            compress_type = 'gz'
+            
+    if compress_type == 'xz':
+        fh = lzma.LZMAFile(fn, mode)
+        if mode == 'w':
+            fh = Duck(write=lambda s, write=fh.write: s != '' and write(s),
+                      close=fh.close)
+        return fh
+    elif compress_type == 'bz2':
+        return bz2.BZ2File(fn, mode)
+    elif compress_type == 'gz':
+        return _gzipOpen(fn, mode)
+    else:
+        raise MDError, "Unknown compression type %s" % compress_type
+    
 def returnFD(filename):
     try:
         fdno = os.open(filename, os.O_RDONLY)
@@ -124,15 +191,28 @@ def encodefiletypelist(filetypelist):
     return result
 
 def split_list_into_equal_chunks(seq, num_chunks):
-    avg = len(seq) / float(num_chunks)
-    out = []
-    last = 0.0
-    while last < len(seq):
-        out.append(seq[int(last):int(last + avg)])
-        last += avg
-
+    """it's used on sorted input which is then merged in order"""
+    out = [[] for i in range(num_chunks)]
+    for i, item in enumerate(seq):
+        out[i % num_chunks].append(item)
     return out
 
+def num_cpus_online(unknown=1):
+    if not hasattr(os, "sysconf"):
+        return unknown
+
+    if not os.sysconf_names.has_key("SC_NPROCESSORS_ONLN"):
+        return unknown
+
+    ncpus = os.sysconf("SC_NPROCESSORS_ONLN")
+    try:
+        if int(ncpus) > 0:
+            return ncpus
+    except:
+        pass
+
+    return unknown
+
 
 class MDError(Exception):
     def __init__(self, value=None):
diff --git a/createrepo/yumbased.py b/createrepo/yumbased.py
index ac06196..f87ac6d 100644
--- a/createrepo/yumbased.py
+++ b/createrepo/yumbased.py
@@ -16,6 +16,11 @@
 
 
 import os
+def _get_umask():
+   oumask = os.umask(0)
+   os.umask(oumask)
+   return oumask
+_b4rpm_oumask = _get_umask()
 import rpm
 import types
 
@@ -86,6 +91,9 @@ class CreateRepoPackage(YumLocalPackage):
                 csumo = os.fdopen(csumo, 'w', -1)
                 csumo.write(checksum)
                 csumo.close()
+                #  tempfile forces 002 ... we want to undo that, so that users
+                # can share the cache. BZ 833350.
+                os.chmod(tmpfilename, 0666 ^ _b4rpm_oumask)
                 os.rename(tmpfilename, csumfile)
             except:
                 pass
diff --git a/docs/createrepo.8 b/docs/createrepo.8
index e3c4c3b..ff359de 100644
--- a/docs/createrepo.8
+++ b/docs/createrepo.8
@@ -53,7 +53,8 @@ gullible).
 Don't generate repo metadata, if their timestamps are newer than its rpms.
 This option decreases the processing time drastically again, if you happen
 to run it on an unmodified repo, but it is (currently) mutual exclusive
-with the --split option.
+with the --split option. NOTE: This command will not notice when 
+packages have been removed from repo. Use --update to handle that.
 .br
 .IP "\fB\--split\fP"
 Run in split media mode. Rather than pass a single directory, take a set of
@@ -104,7 +105,16 @@ Tells createrepo to generate deltarpms and the delta metadata
 paths to look for older pkgs to delta against. Can be specified multiple times
 .IP "\fB\--num-deltas\fP int"
 the number of older versions to make deltas against. Defaults to 1
-
+.IP "\fB\--read-pkgs-list\fP READ_PKGS_LIST
+output the paths to the pkgs actually read useful with  --update
+.IP "\fB\--max-delta-rpm-size\fP MAX_DELTA_RPM_SIZE
+max size of an rpm that to run deltarpm against (in bytes)
+.IP "\fB\--workers\fP WORKERS
+number of workers to spawn to read rpms
+.IP "\fB\--compress-type\fP
+specify which compression method to use: compat (default),
+xz (may not be available), gz, bz2.
+.IP
 
 .SH "EXAMPLES"
 Here is an example of a repository with a groups file. Note that the
diff --git a/genpkgmetadata.py b/genpkgmetadata.py
index 8c98191..c46e441 100755
--- a/genpkgmetadata.py
+++ b/genpkgmetadata.py
@@ -37,6 +37,12 @@ def parse_args(args, conf):
        Sanity check all the things being passed in.
     """
 
+    def_workers = os.nice(0)
+    if def_workers > 0:
+        def_workers = 1 # We are niced, so just use a single worker.
+    else:
+        def_workers = 0 # zoooom....
+
     _def   = yum.misc._default_checksums[0]
     _avail = yum.misc._available_checksums
     parser = OptionParser(version = "createrepo %s" % createrepo.__version__)
@@ -100,6 +106,8 @@ def parse_args(args, conf):
     parser.add_option("--simple-md-filenames", dest="simple_md_filenames",
         help="do not include the file's checksum in the filename, helps with proxies",
         default=False, action="store_true")
+    parser.add_option("--retain-old-md", default=0, type='int', dest='retain_old_md',
+        help="keep around the latest (by timestamp) N copies of the old repodata")
     parser.add_option("--distro", default=[], action="append",
         help="distro tag and optional cpeid: --distro" "'cpeid,textname'")
     parser.add_option("--content", default=[], dest='content_tags',
@@ -119,10 +127,15 @@ def parse_args(args, conf):
     parser.add_option("--max-delta-rpm-size", default=100000000,
         dest='max_delta_rpm_size', type='int',
         help="max size of an rpm that to run deltarpm against (in bytes)")
-
-    parser.add_option("--workers", default=1,
+    parser.add_option("--workers", default=def_workers,
         dest='workers', type='int',
         help="number of workers to spawn to read rpms")
+    parser.add_option("--xz", default=False,
+        action="store_true",
+        help="use xz for repodata compression")
+    parser.add_option("--compress-type", default='compat', dest="compress_type",
+        help="which compression type to use")
+        
     
     (opts, argsleft) = parser.parse_args(args)
     if len(argsleft) > 1 and not opts.split:
@@ -138,6 +151,9 @@ def parse_args(args, conf):
     else:
         directories = argsleft
 
+    if opts.workers >= 128:
+        errorprint(_('Warning: More than 128 workers is a lot. Limiting.'))
+        opts.workers = 128
     if opts.sumtype == 'sha1':
         errorprint(_('Warning: It is more compatible to use sha instead of sha1'))
 
@@ -155,6 +171,11 @@ def parse_args(args, conf):
     
     if opts.nodatabase:
         opts.database = False
+    
+    # xz is just a shorthand for compress_type
+    if opts.xz and opts.compress_type == 'compat':
+        opts.compress_type='xz'
+        
         
     # let's switch over to using the conf object - put all the opts into it
     for opt in parser.option_list:
@@ -240,6 +261,7 @@ def main(args):
             if mdgen.checkTimeStamps():
                 if mdgen.conf.verbose:
                     print _('repo is up to date')
+                mdgen._cleanup_tmp_repodata_dir()
                 sys.exit(0)
 
         if conf.profile:
diff --git a/mergerepo.py b/mergerepo.py
index 05e5f5e..80cb1a8 100755
--- a/mergerepo.py
+++ b/mergerepo.py
@@ -18,6 +18,7 @@
 
 import sys
 import createrepo.merge
+from createrepo.utils import MDError
 from optparse import OptionParser
 
 #TODO:
@@ -47,6 +48,9 @@ def parse_args(args):
                       help="Do not merge group(comps) metadata")
     parser.add_option("", "--noupdateinfo", default=False, action="store_true",
                       help="Do not merge updateinfo metadata")
+    parser.add_option("--compress-type", default=None, dest="compress_type",
+                      help="which compression type to use")
+                      
     (opts, argsleft) = parser.parse_args(args)
 
     if len(opts.repos) < 2:
@@ -77,9 +81,14 @@ def main(args):
         rmbase.groups = False
     if opts.noupdateinfo:
         rmbase.updateinfo = False
-
-    rmbase.merge_repos()
-    rmbase.write_metadata()
-
+    if opts.compress_type:
+        rmbase.mdconf.compress_type = opts.compress_type
+    try:
+        rmbase.merge_repos()
+        rmbase.write_metadata()
+    except MDError, e:
+        print >> sys.stderr, "Could not merge repos: %s" % e
+        sys.exit(1)
+        
 if __name__ == "__main__":
     main(sys.argv[1:])
diff --git a/modifyrepo.py b/modifyrepo.py
index 17094a4..bf1eec0 100755
--- a/modifyrepo.py
+++ b/modifyrepo.py
@@ -1,11 +1,15 @@
 #!/usr/bin/python
-# This tools is used to insert arbitrary metadata into an RPM repository.
+# This tool is used to manipulate arbitrary metadata in a RPM repository.
 # Example:
 #           ./modifyrepo.py updateinfo.xml myrepo/repodata
+#           or
+#           ./modifyrepo.py --remove updateinfo.xml myrepo/repodata
 # or in Python:
 #           >>> from modifyrepo import RepoMetadata
 #           >>> repomd = RepoMetadata('myrepo/repodata')
 #           >>> repomd.add('updateinfo.xml')
+#           or
+#           >>> repomd.remove('updateinfo.xml')
 #
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -20,11 +24,13 @@
 # (C) Copyright 2006  Red Hat, Inc.
 # Luke Macken <lmacken@redhat.com>
 # modified by Seth Vidal 2008
+# modified by Daniel Mach 2011
 
 import os
 import sys
 from createrepo import __version__
-from createrepo.utils import checksum_and_rename, GzipFile, MDError
+from createrepo.utils import checksum_and_rename, compressOpen, MDError
+from createrepo.utils import _available_compression
 from yum.misc import checksum
 
 from yum.repoMDObject import RepoMD, RepoMDError, RepoData
@@ -39,6 +45,8 @@ class RepoMetadata:
         self.repodir = os.path.abspath(repo)
         self.repomdxml = os.path.join(self.repodir, 'repomd.xml')
         self.checksum_type = 'sha256'
+        self.compress = False
+        self.compress_type = _available_compression[-1] # best available
 
         if not os.path.exists(self.repomdxml):
             raise MDError, '%s not found' % self.repomdxml
@@ -49,6 +57,35 @@ class RepoMetadata:
         except RepoMDError, e:
             raise MDError, 'Could not parse %s' % self.repomdxml
 
+    def _get_mdtype(self, mdname, mdtype=None):
+        """ Get mdtype from existing mdtype or from a mdname. """
+        if mdtype:
+            return mdtype
+        return mdname.split('.')[0]
+
+    def _print_repodata(self, repodata):
+        """ Print repodata details. """
+        print "           type =", repodata.type
+        print "       location =", repodata.location[1]
+        print "       checksum =", repodata.checksum[1]
+        print "      timestamp =", repodata.timestamp
+        print "  open-checksum =", repodata.openchecksum[1]
+
+    def _write_repomd(self):
+        """ Write the updated repomd.xml. """
+        outmd = file(self.repomdxml, 'w')
+        outmd.write(self.repoobj.dump_xml())
+        outmd.close()
+        print "Wrote:", self.repomdxml
+
+    def _remove_repodata_file(self, repodata):
+        """ Remove a file specified in repodata location """
+        try:
+            os.remove(repodata.location[1])
+        except OSError, ex:
+            if ex.errno != 2:
+                # continue on a missing file
+                raise MDError("could not remove file %s" % repodata.location[1])
 
     def add(self, metadata, mdtype=None):
         """ Insert arbitrary metadata into this repository.
@@ -63,8 +100,8 @@ class RepoMetadata:
             mdname = 'updateinfo.xml'
         elif isinstance(metadata, str):
             if os.path.exists(metadata):
-                if metadata.endswith('.gz'):
-                    oldmd = GzipFile(filename=metadata, mode='rb')
+                if metadata.split('.')[-1] in ('gz', 'bz2', 'xz'):
+                    oldmd = compressOpen(metadata, mode='rb')
                 else:
                     oldmd = file(metadata, 'r')
                 md = oldmd.read()
@@ -75,14 +112,19 @@ class RepoMetadata:
         else:
             raise MDError, 'invalid metadata type'
 
+        do_compress = False
         ## Compress the metadata and move it into the repodata
-        if not mdname.endswith('.gz'):
-            mdname += '.gz'
-        if not mdtype:
-            mdtype = mdname.split('.')[0]
-            
+        if self.compress or not mdname.split('.')[-1] in ('gz', 'bz2', 'xz'):
+            do_compress = True
+            mdname += '.' + self.compress_type
+        mdtype = self._get_mdtype(mdname, mdtype)
+
         destmd = os.path.join(self.repodir, mdname)
-        newmd = GzipFile(filename=destmd, mode='wb')
+        if do_compress:
+            newmd = compressOpen(destmd, mode='wb', compress_type=self.compress_type)
+        else:
+            newmd = open(destmd, 'wb')
+            
         newmd.write(md)
         newmd.close()
         print "Wrote:", destmd
@@ -91,11 +133,8 @@ class RepoMetadata:
         csum, destmd = checksum_and_rename(destmd, self.checksum_type)
         base_destmd = os.path.basename(destmd)
 
-
-        ## Remove any stale metadata
-        if mdtype in self.repoobj.repoData:
-            del self.repoobj.repoData[mdtype]
-            
+        # Remove any stale metadata
+        old_rd = self.repoobj.repoData.pop(mdtype, None)
 
         new_rd = RepoData()
         new_rd.type = mdtype
@@ -105,18 +144,28 @@ class RepoMetadata:
         new_rd.size = str(os.stat(destmd).st_size)
         new_rd.timestamp = str(os.stat(destmd).st_mtime)
         self.repoobj.repoData[new_rd.type] = new_rd
-        
-        print "           type =", new_rd.type
-        print "       location =", new_rd.location[1]
-        print "       checksum =", new_rd.checksum[1]
-        print "      timestamp =", new_rd.timestamp
-        print "  open-checksum =", new_rd.openchecksum[1]
-
-        ## Write the updated repomd.xml
-        outmd = file(self.repomdxml, 'w')
-        outmd.write(self.repoobj.dump_xml())
-        outmd.close()
-        print "Wrote:", self.repomdxml
+        self._print_repodata(new_rd)
+        self._write_repomd()
+
+        if old_rd is not None and old_rd.location[1] != new_rd.location[1]:
+            # remove the old file when overwriting metadata
+            # with the same mdtype but different location
+            self._remove_repodata_file(old_rd)
+
+    def remove(self, metadata, mdtype=None):
+        """ Remove metadata from this repository. """
+        mdname = metadata
+        mdtype = self._get_mdtype(mdname, mdtype)
+
+        old_rd = self.repoobj.repoData.pop(mdtype, None)
+        if old_rd is None:
+            print "Metadata not found: %s" % mdtype
+            return
+
+        self._remove_repodata_file(old_rd)
+        print "Removed:"
+        self._print_repodata(old_rd)
+        self._write_repomd()
 
 
 def main(args):
@@ -124,7 +173,13 @@ def main(args):
     # query options
     parser.add_option("--mdtype", dest='mdtype',
                       help="specific datatype of the metadata, will be derived from the filename if not specified")
-    parser.usage = "modifyrepo [options] <input_metadata> <output repodata>"
+    parser.add_option("--remove", action="store_true",
+                      help="remove specified file from repodata")
+    parser.add_option("--compress", action="store_true", default=False,
+                      help="compress the new repodata before adding it to the repo")
+    parser.add_option("--compress-type", dest='compress_type', default='gz',
+                      help="compression format to use")
+    parser.usage = "modifyrepo [options] [--remove] <input_metadata> <output repodata>"
     
     (opts, argsleft) = parser.parse_args(args)
     if len(argsleft) != 2:
@@ -137,11 +192,28 @@ def main(args):
     except MDError, e:
         print "Could not access repository: %s" % str(e)
         return 1
+
+
+    repomd.compress = opts.compress
+    if opts.compress_type in _available_compression:
+        repomd.compress_type = opts.compress_type
+
+    # remove
+    if opts.remove:
+        try:
+            repomd.remove(metadata)
+        except MDError, ex:
+            print "Could not remove metadata: %s" % (metadata, str(ex))
+            return 1
+        return
+
+    # add
     try:
         repomd.add(metadata, mdtype=opts.mdtype)
     except MDError, e:
         print "Could not add metadata from file %s: %s" % (metadata, str(e))
         return 1
+    
 
 if __name__ == '__main__':
     ret = main(sys.argv[1:])
diff --git a/worker.py b/worker.py
index eb35ef7..fe6758f 100755
--- a/worker.py
+++ b/worker.py
@@ -5,6 +5,7 @@ import yum
 import createrepo
 import os
 import rpmUtils
+import re
 from optparse import OptionParser
 
 
@@ -23,6 +24,8 @@ def main(args):
     parser = OptionParser()
     parser.add_option('--tmpmdpath', default=None, 
                 help="path where the outputs should be dumped for this worker")
+    parser.add_option('--pkglist', default=None, 
+                help="file to read the pkglist from in lieu of all of them on the cli")
     parser.add_option("--pkgoptions", default=[], action='append',
                 help="pkgoptions in the format of key=value")
     parser.add_option("--quiet", default=False, action='store_true',
@@ -36,10 +39,6 @@ def main(args):
     opts, pkgs = parser.parse_args(args)
     external_data = {'_packagenumber': 1}
     globalopts = {}
-    if not opts.tmpmdpath:
-        print >> sys.stderr, "tmpmdpath required for destination files"
-        sys.exit(1)
-    
     
     for strs in opts.pkgoptions:
         k,v = strs.split('=')
@@ -64,15 +63,34 @@ def main(args):
     
     reldir = external_data['_reldir']
     ts = rpmUtils.transaction.initReadOnlyTransaction()
-    pri = open(opts.tmpmdpath + '/primary.xml' , 'w')
-    fl = open(opts.tmpmdpath  + '/filelists.xml' , 'w')
-    other = open(opts.tmpmdpath  + '/other.xml' , 'w')
-    
-    
+    if opts.tmpmdpath:
+        files = [open(opts.tmpmdpath + '/%s.xml' % i, 'w')
+                 for i in ('primary', 'filelists', 'other')]
+        def output(*xml):
+            for fh, buf in zip(files, xml):
+                fh.write(buf)
+    else:
+        def output(*xml):
+            buf = ' '.join(str(len(i)) for i in xml)
+            sys.stdout.write('*** %s\n' % buf)
+            for buf in xml:
+                sys.stdout.write(buf)
+
+    if opts.pkglist:
+        for line in open(opts.pkglist,'r').readlines():
+            line = line.strip()
+            if re.match('^\s*\#.*', line) or re.match('^\s*$', line):
+                continue
+            pkgs.append(line)
+
+    clog_limit=globalopts.get('clog_limit', None)
+    if clog_limit is not None:
+         clog_limit = int(clog_limit)
     for pkgfile in pkgs:
         pkgpath = reldir + '/' + pkgfile
         if not os.path.exists(pkgpath):
             print >> sys.stderr, "File not found: %s" % pkgpath
+            output()
             continue
 
         try:
@@ -80,20 +98,17 @@ def main(args):
                 print "reading %s" % (pkgfile)
 
             pkg = createrepo.yumbased.CreateRepoPackage(ts, package=pkgpath, 
-                                                        external_data=external_data)
-            pri.write(pkg.xml_dump_primary_metadata())
-            fl.write(pkg.xml_dump_filelists_metadata())
-            other.write(pkg.xml_dump_other_metadata(clog_limit=
-                                            globalopts.get('clog_limit', None)))
+                                sumtype=globalopts.get('sumtype', None), 
+                                external_data=external_data)
+            output(pkg.xml_dump_primary_metadata(),
+                   pkg.xml_dump_filelists_metadata(),
+                   pkg.xml_dump_other_metadata(clog_limit=clog_limit))
         except yum.Errors.YumBaseError, e:
             print >> sys.stderr, "Error: %s" % e
+            output()
             continue
         else:
             external_data['_packagenumber']+=1
         
-    pri.close()
-    fl.close()
-    other.close()
-    
 if __name__ == "__main__":
     main(sys.argv[1:])