b=15962 disable statahead by default due to important races found in the code

diff --git a/lustre/ChangeLog b/lustre/ChangeLog
index 9956537..5744be9 100644 (file)
--- a/lustre/ChangeLog
+++ b/lustre/ChangeLog
@@ -17,6 +17,11 @@ Bugzilla   : 23081
 Description: llap pages are moved to head of LRU list instead of tail
 
 Severity   : normal
+Bugzilla   : 15962
+Description: disable statahead by default due to important races found in the
+             statahead implementation.
+
+Severity   : normal
 Bugzilla   : 21804
 Description: release request ref through ptlrpc_server_drop_request()
 Details    : make sure the request is protected by rq_refcount while

diff --git a/lustre/llite/llite_lib.c b/lustre/llite/llite_lib.c
index 4c60593..dcc0862 100644 (file)
--- a/lustre/llite/llite_lib.c
+++ b/lustre/llite/llite_lib.c
@@ -205,8 +205,9 @@ static struct ll_sb_info *ll_init_sbi(void)
                 spin_lock_init(&sbi->ll_rw_extents_info.pp_extents[i].pp_w_hist.oh_lock);
         }
 
-        /* metadata statahead is enabled by default */
-        sbi->ll_sa_max = LL_SA_RPC_DEF;
+        /* metadata statahead is disabled by default */
+        sbi->ll_sa_max = 0;
+        /* sbi->ll_sa_max = LL_SA_RPC_DEF; */
 
         RETURN(sbi);