This is a note to let you know that I've just added the patch titled

    dm bufio: update last_accessed when relinking a buffer

to the 3.17-stable tree which can be found at:
    
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     dm-bufio-update-last_accessed-when-relinking-a-buffer.patch
and it can be found in the queue-3.17 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.


>From eb76faf53b1ff7a77ce3f78cc98ad392ac70c2a0 Mon Sep 17 00:00:00 2001
From: Joe Thornber <[email protected]>
Date: Tue, 30 Sep 2014 09:32:46 +0100
Subject: dm bufio: update last_accessed when relinking a buffer

From: Joe Thornber <[email protected]>

commit eb76faf53b1ff7a77ce3f78cc98ad392ac70c2a0 upstream.

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 <[email protected]>
Signed-off-by: Mikulas Patocka <[email protected]>
Signed-off-by: Mike Snitzer <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 drivers/md/dm-bufio.c |    1 +
 1 file changed, 1 insertion(+)

--- a/drivers/md/dm-bufio.c
+++ b/drivers/md/dm-bufio.c
@@ -465,6 +465,7 @@ static void __relink_lru(struct dm_buffe
        c->n_buffers[dirty]++;
        b->list_mode = dirty;
        list_move(&b->lru_list, &c->lru[dirty]);
+       b->last_accessed = jiffies;
 }
 
 /*----------------------------------------------------------------


Patches currently in stable-queue which might be from [email protected] are

queue-3.17/dm-bufio-update-last_accessed-when-relinking-a-buffer.patch
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to