1 ; https://github.com/bobrik/linux/pull/2
2 From 1910e1157eb4b455b877a813f0a1b786dcbf799c Mon Sep 17 00:00:00 2001
3 From: Ivan Babrou <ibobrik@gmail.com>
4 Date: Tue, 27 Nov 2018 14:37:25 -0800
5 Subject: [PATCH] xfs: add a sysctl to disable memory reclaim participation
7 XFS may try to flush dirty inodes in reclaim and it slows things down
8 considerably, especially in high page cache and slow disk environment.
10 This sysctl allows to exclude XFS from kswapd and direct reclaim.
12 See: https://marc.info/?t=154345187200003
13 diff --git a/Documentation/admin-guide/xfs.rst b/Documentation/admin-guide/xfs.rst
14 index 3b9b5c149f322..b33a4822f879c 100644
15 --- a/Documentation/admin-guide/xfs.rst
16 +++ b/Documentation/admin-guide/xfs.rst
17 @@ -331,6 +331,12 @@ The following sysctls are available for the XFS filesystem:
18 is to control the rate at which the allocator moves between
19 allocation groups when allocating extents for new files.
21 + fs.xfs.memory_reclaim (Min: 0 Default: 2 Max: 2)
22 + Set memory reclaim strategy:
23 + 0: no inode reclaim (background reclaim is still enabled)
24 + 1: async inode reclaim of clean inodes only
25 + 2: sync inode reclaim (includes synchronous writes)
30 diff --git a/fs/xfs/xfs_globals.c b/fs/xfs/xfs_globals.c
31 index 3e1cc3001bcbf..2927cc2b12b57 100644
32 --- a/fs/xfs/xfs_globals.c
33 +++ b/fs/xfs/xfs_globals.c
34 @@ -43,6 +43,7 @@ xfs_param_t xfs_params = {
35 .fstrm_timer = { 1, 30*100, 3600*100},
36 .eofb_timer = { 1, 300, 3600*24},
37 .cowb_timer = { 1, 1800, 3600*24},
38 + .memory_reclaim = { 0, 2, 2, },
41 struct xfs_globals xfs_globals = {
42 diff --git a/fs/xfs/xfs_icache.c b/fs/xfs/xfs_icache.c
43 index 544b5211221cd..54fcf1af7e3f5 100644
44 --- a/fs/xfs/xfs_icache.c
45 +++ b/fs/xfs/xfs_icache.c
46 @@ -1380,7 +1380,11 @@ xfs_reclaim_inodes_nr(
47 xfs_reclaim_work_queue(mp);
48 xfs_ail_push_all(mp->m_ail);
50 - return xfs_reclaim_inodes_ag(mp, SYNC_TRYLOCK | SYNC_WAIT, &nr_to_scan);
51 + int flags = SYNC_TRYLOCK;
52 + if (xfs_memory_reclaim == XFS_MEMORY_RECLAIM_SYNC)
55 + return xfs_reclaim_inodes_ag(mp, flags, &nr_to_scan);
59 diff --git a/fs/xfs/xfs_icache.h b/fs/xfs/xfs_icache.h
60 index bff4d85e54984..2547c0d85e5a1 100644
61 --- a/fs/xfs/xfs_icache.h
62 +++ b/fs/xfs/xfs_icache.h
63 @@ -54,6 +54,12 @@ struct xfs_eofblocks {
65 #define XFS_AGITER_INEW_WAIT 0x1 /* wait on new inodes */
68 + XFS_MEMORY_RECLAIM_NONE = 0,
69 + XFS_MEMORY_RECLAIM_ASYNC,
70 + XFS_MEMORY_RECLAIM_SYNC,
73 int xfs_iget(struct xfs_mount *mp, struct xfs_trans *tp, xfs_ino_t ino,
74 uint flags, uint lock_flags, xfs_inode_t **ipp);
76 diff --git a/fs/xfs/xfs_linux.h b/fs/xfs/xfs_linux.h
77 index dcd1292664b34..3cddbffaa8cb4 100644
78 --- a/fs/xfs/xfs_linux.h
79 +++ b/fs/xfs/xfs_linux.h
80 @@ -110,6 +110,7 @@ typedef __u32 xfs_nlink_t;
81 #define xfs_fstrm_centisecs xfs_params.fstrm_timer.val
82 #define xfs_eofb_secs xfs_params.eofb_timer.val
83 #define xfs_cowb_secs xfs_params.cowb_timer.val
84 +#define xfs_memory_reclaim xfs_params.memory_reclaim.val
86 #define current_cpu() (raw_smp_processor_id())
87 #define current_pid() (current->pid)
88 diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
89 index 0b0282d2f011c..232e3706a0a60 100644
90 --- a/fs/xfs/xfs_super.c
91 +++ b/fs/xfs/xfs_super.c
92 @@ -1828,6 +1828,8 @@ xfs_fs_nr_cached_objects(
93 /* Paranoia: catch incorrect calls during mount setup or teardown */
94 if (WARN_ON_ONCE(!sb->s_fs_info))
96 + if (xfs_memory_reclaim == XFS_MEMORY_RECLAIM_NONE)
98 return xfs_reclaim_inodes_count(XFS_M(sb));
101 diff --git a/fs/xfs/xfs_sysctl.c b/fs/xfs/xfs_sysctl.c
102 index afe1f66aaa698..ccf0d1759c215 100644
103 --- a/fs/xfs/xfs_sysctl.c
104 +++ b/fs/xfs/xfs_sysctl.c
105 @@ -193,6 +193,15 @@ static struct ctl_table xfs_table[] = {
106 .extra1 = &xfs_params.cowb_timer.min,
107 .extra2 = &xfs_params.cowb_timer.max,
110 + .procname = "memory_reclaim",
111 + .data = &xfs_params.memory_reclaim.val,
112 + .maxlen = sizeof(int),
114 + .proc_handler = proc_dointvec_minmax,
115 + .extra1 = &xfs_params.memory_reclaim.min,
116 + .extra2 = &xfs_params.memory_reclaim.max,
118 /* please keep this the last entry */
119 #ifdef CONFIG_PROC_FS
121 diff --git a/fs/xfs/xfs_sysctl.h b/fs/xfs/xfs_sysctl.h
122 index 82afee005140a..eaf3addd486e7 100644
123 --- a/fs/xfs/xfs_sysctl.h
124 +++ b/fs/xfs/xfs_sysctl.h
125 @@ -49,6 +49,7 @@ typedef struct xfs_param {
126 xfs_sysctl_val_t fstrm_timer; /* Filestream dir-AG assoc'n timeout. */
127 xfs_sysctl_val_t eofb_timer; /* Interval between eofb scan wakeups */
128 xfs_sysctl_val_t cowb_timer; /* Interval between cowb scan wakeups */
129 + xfs_sysctl_val_t memory_reclaim;/* Memory reclaim policy. */
133 @@ -89,6 +90,7 @@ enum {
135 XFS_INHERIT_NODFRG = 21,
136 XFS_FILESTREAM_TIMER = 22,
137 + XFS_MEMORY_RECLAIM = 23,
140 extern xfs_param_t xfs_params;