From 27c0f68f0745218cec70f19ba7560c8c5fc3f817 Mon Sep 17 00:00:00 2001 From: Shaohua Li Date: Wed, 9 Apr 2014 11:25:47 +0800 Subject: [PATCH] raid5: make_request does less prepare wait In NUMA machine, prepare_to_wait/finish_wait in make_request exposes a lot of contention for sequential workload (or big request size workload). For such workload, each bio includes several stripes. So we can just do prepare_to_wait/finish_wait once for the whold bio instead of every stripe. This reduces the lock contention completely for such workload. Random workload might have the similar lock contention too, but I didn't see it yet, maybe because my stroage is still not fast enough. Signed-off-by: Shaohua Li Signed-off-by: NeilBrown --- Reading git-format-patch failed