lkml.org 
[lkml]   [2006]   [Sep]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [2.6.17.4] slabinfo.buffer_head increases
On Tue, 12 Sep 2006, Nick Piggin wrote:

> Guennadi Liakhovetski wrote:
>
>>> On Mon, 10 Jul 2006, Guennadi Liakhovetski wrote:
>>>
>>>> I am obsering a steadily increasing buffer_head value in slabinfo under
>>>> 2.6.17.4. I searched the net / archives and didn't find anything
>>>> directly relevant. Does anyone have an idea or how shall we debug it?
>>>
>>
>> The problem is still there under 2.6.18-rc2. I narrowed it down to ext3
>> journal. To reproduce one just has to mount an ext3 partition and perform
>> (write) accesses to it. A loop { touch /mnt/foo; sleep 1; } suffices - just
>> let it run for a couple of minutes and monitor buffer_head in
>> /proc/slabinfo. If you mount it as ext2 the problem is gone.
>
>
> What data mode is ext3 mounted with?

Default, i.e., ordered, I guess.

> Is the memory reclaimable? If yes, is it a problem?

Yes, that's why I later wrote that the problem is not real. It was hard to
see as we had a lot of free RAM on the system, the system was idle apart
from one script that only did "touch x" periodically with the same "x"
and the buffer_head slab was growing very steadily. Unlike with ext2 /
reiserfs. That's why I decided it was not ok. But the memory is
reclaimable, so, seems like not a problem. Just a bit odd that such a
"harmless" operation causes a steady growth of buffer_heads...

Thanks
Guennadi
---------------------------------
Guennadi Liakhovetski, Ph.D.
DSA Daten- und Systemtechnik GmbH
Pascalstr. 28
D-52076 Aachen
Germany
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2006-09-12 19:19    [W:0.048 / U:0.312 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site