diff options
| author | Joe Thornber <ejt@redhat.com> | 2014-09-30 09:32:46 +0100 |
|---|---|---|
| committer | Mike Snitzer <snitzer@redhat.com> | 2014-10-05 20:03:37 -0400 |
| commit | eb76faf53b1ff7a77ce3f78cc98ad392ac70c2a0 (patch) | |
| tree | 193ccb7f0b8f9e098a659ccecb1d1b2f9244441c | |
| parent | 48cf06bc5f508d5f71bc0fd7530daebb12a48428 (diff) | |
dm bufio: update last_accessed when relinking a buffer
The 'last_accessed' member of the dm_buffer structure was only set when
the the buffer was created. This led to each buffer being discarded
after dm_bufio_max_age time even if it was used recently. In practice
this resulted in all thinp metadata being evicted soon after being read
-- this is particularly problematic for metadata intensive workloads
like multithreaded small random IO.
'last_accessed' is now updated each time the buffer is moved to the head
of the LRU list, so the buffer is now properly discarded if it was not
used in dm_bufio_max_age time.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org # v3.2+
| -rw-r--r-- | drivers/md/dm-bufio.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/drivers/md/dm-bufio.c b/drivers/md/dm-bufio.c index ab472c557d18..eab64bcaab66 100644 --- a/drivers/md/dm-bufio.c +++ b/drivers/md/dm-bufio.c @@ -465,6 +465,7 @@ static void __relink_lru(struct dm_buffer *b, int dirty) c->n_buffers[dirty]++; b->list_mode = dirty; list_move(&b->lru_list, &c->lru[dirty]); + b->last_accessed = jiffies; } /*---------------------------------------------------------------- |