diff options
| author | Tim Chase <[email protected]> | 2015-04-14 01:06:40 -0400 |
|---|---|---|
| committer | Brian Behlendorf <[email protected]> | 2015-04-14 12:19:22 -0700 |
| commit | 5074bfe8ade40ddc64cba5526eb1333a73621e92 (patch) | |
| tree | 34a43dc45c9d1837df53eac01e552d75bab9828a | |
| parent | d07a16360c1ee219b8820f80d035e56a18c58b84 (diff) | |
Allocate zfs_znode_cache on the Linux slab
The Linux slab, in general, performs better than the SPl slab in cases
where a lot of objects are allocated and fragmentation is likely present.
This patch fixes pathologically bad behavior in cases where the ARC is
filled with mostly metadata and a user program needs to allocate and
dirty enough memory which would require an insignificant amount of the
ARC to be reclaimed.
If zfs_znode_cache is on the SPL slab, the system may spin for a very
long time trying to reclaim sufficient memory. If it is on the Linux
slab, the behavior has been observed to be much more predictible; the
memory is reclaimed more efficiently.
Signed-off-by: Tim Chase <[email protected]>
Signed-off-by: Brian Behlendorf <[email protected]>
Issue #3283
| -rw-r--r-- | module/zfs/zfs_znode.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/module/zfs/zfs_znode.c b/module/zfs/zfs_znode.c index c931a72c3..0c0091f04 100644 --- a/module/zfs/zfs_znode.c +++ b/module/zfs/zfs_znode.c @@ -147,12 +147,14 @@ void zfs_znode_init(void) { /* - * Initialize zcache + * Initialize zcache. The KMC_SLAB hint is used in order that it be + * backed by kmalloc() when on the Linux slab in order that any + * wait_on_bit() operations on the related inode operate properly. */ ASSERT(znode_cache == NULL); znode_cache = kmem_cache_create("zfs_znode_cache", sizeof (znode_t), 0, zfs_znode_cache_constructor, - zfs_znode_cache_destructor, NULL, NULL, NULL, KMC_KMEM); + zfs_znode_cache_destructor, NULL, NULL, NULL, KMC_SLAB); } void |