LU-5240 obdclass: Increase minimum LU Cache for ZFS

If the lu cache is too small threads will thrash for data including
the OI tables and other important metadata.

Test-Parameters: mdsfilesystemtype=zfs mdtfilesystemtype=zfs ostfilesystemtype=zfs testgroup=review-zfs
Signed-off-by: Nathaniel Clark <nathaniel.l.clark@intel.com>
Change-Id: I1ce7ef9a160c8b028be0d3c9671a0b347cbe3331
Reviewed-on: http://review.whamcloud.com/10802
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>
Tested-by: Jenkins

diff --git a/lustre/obdclass/lu_object.c b/lustre/obdclass/lu_object.c
index fe43331..91b3693 100644 (file)
--- a/lustre/obdclass/lu_object.c
+++ b/lustre/obdclass/lu_object.c
@@ -71,7 +71,8 @@ enum {
 #define        LU_CACHE_NR_UNLIMITED           -1
 #define        LU_CACHE_NR_DEFAULT             LU_CACHE_NR_UNLIMITED
 #define        LU_CACHE_NR_LDISKFS_LIMIT       LU_CACHE_NR_UNLIMITED
-#define        LU_CACHE_NR_ZFS_LIMIT           256
+/** This is set to roughly (20 * OSS_NTHRS_MAX) to prevent thrashing */
+#define        LU_CACHE_NR_ZFS_LIMIT           10240
 
 #define LU_SITE_BITS_MIN    12
 #define LU_SITE_BITS_MAX    24