From: Zdenek Kabelac <zdenek.kabelac@gmail.com>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Zlatko Calusic <zlatko.calusic@iskon.hr>,
Johannes Weiner <hannes@cmpxchg.org>,
Mel Gorman <mgorman@suse.de>, linux-mm <linux-mm@kvack.org>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: kswapd craziness in 3.7
Date: Sun, 09 Dec 2012 22:59:47 +0100 [thread overview]
Message-ID: <50C509D3.3070108@gmail.com> (raw)
In-Reply-To: <alpine.LFD.2.02.1212081651270.4593@air.linux-foundation.org>
Dne 9.12.2012 02:01, Linus Torvalds napsal(a):
>
>
> On Sat, 8 Dec 2012, Zlatko Calusic wrote:
>>
>> Or sooner... in short: nothing's changed!
>>
>> On a 4GB RAM system, where applications use close to 2GB, kswapd likes to keep
>> around 1GB free (unused), leaving only 1GB for page/buffer cache. If I force
>> bigger page cache by reading a big file and thus use the unused 1GB of RAM,
>> kswapd will soon (in a matter of minutes) evict those (or other) pages out and
>> once again keep unused memory close to 1GB.
>
> Ok, guys, what was the reclaim or kswapd patch during the merge window
> that actually caused all of these insane problems? It seems it was more
> fundamentally buggered than the fifteen-million fixes for kswapd we have
> already picked up.
>
> (Ok, I may be exaggerating the number of patches, but it's starting to
> feel that way - I thought that 3.7 was going to be a calm and easy
> release, but the kswapd issues seem to just keep happening. We've been
> fighting the kswapd changes for a while now.)
>
> Trying to keep a gigabyte free (presumably because that way we have lots
> of high-order alloction pages) is ridiculous. Is it one of the compaction
> changes?
>
> Mel? Ideas?
>
Very true
It's just as simple a making
dd if=/dev/zero of=/tmp/zero bs=1M count=0 seek=1000000
and now
dd if=/tmp/zero of=/dev/null bs=1M
and kswapd fights with dd for CPU time....
Zdenek
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next prev parent reply other threads:[~2012-12-09 21:59 UTC|newest]
Thread overview: 65+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-11-27 20:48 kswapd craziness in 3.7 Johannes Weiner
2012-11-27 20:48 ` [patch] mm: vmscan: fix kswapd endless loop on higher order allocation Johannes Weiner
2012-11-27 20:58 ` kswapd craziness in 3.7 Linus Torvalds
2012-11-27 21:16 ` Rik van Riel
2012-11-27 21:49 ` Johannes Weiner
2012-11-27 22:02 ` Rik van Riel
2012-11-27 22:26 ` Johannes Weiner
2012-11-27 23:19 ` Linus Torvalds
2012-11-28 10:13 ` Mel Gorman
2012-11-28 10:51 ` Thorsten Leemhuis
2012-11-28 16:42 ` Mel Gorman
2012-11-28 22:52 ` Andrew Morton
2012-11-28 23:54 ` Mel Gorman
2012-11-29 0:14 ` Andrew Morton
2012-11-29 15:30 ` Thorsten Leemhuis
2012-11-29 17:05 ` Johannes Weiner
2012-11-30 12:39 ` Thorsten Leemhuis
2012-12-01 0:45 ` Johannes Weiner
2012-12-03 8:30 ` Thorsten Leemhuis
2012-12-03 13:08 ` Fedora repo (was: Re: kswapd craziness in 3.7) Borislav Petkov
2012-12-03 19:42 ` kswapd craziness in 3.7 Johannes Weiner
2012-12-04 21:42 ` Johannes Weiner
2012-12-05 3:01 ` Bruno Wolff III
2012-12-06 17:37 ` Bruno Wolff III
2012-12-06 19:31 ` Linus Torvalds
2012-12-06 19:43 ` Rik van Riel
2012-12-06 20:23 ` Johannes Weiner
2012-12-06 20:32 ` Rik van Riel
2012-12-08 12:06 ` Zlatko Calusic
2012-12-08 21:22 ` Zlatko Calusic
2012-12-09 1:01 ` Linus Torvalds
2012-12-09 21:59 ` Zdenek Kabelac [this message]
2012-12-10 11:03 ` Mel Gorman
2012-12-10 16:39 ` Johannes Weiner
2012-12-10 18:01 ` Mel Gorman
2012-12-10 18:33 ` Zlatko Calusic
2012-12-10 19:13 ` Linus Torvalds
2012-12-10 20:35 ` Zlatko Calusic
2012-12-10 21:28 ` Linus Torvalds
2012-12-10 21:42 ` Borislav Petkov
2012-12-10 21:47 ` Linus Torvalds
2012-12-10 21:54 ` Borislav Petkov
2012-12-10 22:15 ` Zlatko Calusic
2012-12-10 23:27 ` Hugh Dickins
2012-12-11 0:19 ` Zlatko Calusic
2012-12-11 21:56 ` Zlatko Calusic
2012-12-19 22:24 ` Zlatko Calusic
2012-12-10 18:29 ` Zlatko Calusic
2012-12-06 8:09 ` Thorsten Leemhuis
2012-11-27 21:29 ` Johannes Weiner
2012-11-28 13:35 ` Zdenek Kabelac
2012-11-28 14:04 ` Jiri Slaby
2012-11-28 9:45 ` Mel Gorman
2012-12-03 15:23 ` Zdenek Kabelac
2012-12-03 19:18 ` Johannes Weiner
2012-12-04 9:05 ` Zdenek Kabelac
2012-12-04 9:15 ` Jiri Slaby
2012-12-04 16:11 ` Johannes Weiner
2012-12-04 16:22 ` Jiri Slaby
2012-12-04 19:50 ` Johannes Weiner
2012-12-08 10:35 ` Jiri Slaby
2012-12-04 16:15 ` Johannes Weiner
2012-12-06 13:51 ` Zdenek Kabelac
2012-12-03 13:14 ` Jiri Slaby
2012-12-04 8:55 ` Jiri Slaby
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