Re: kswapd craziness in 3.7
[Posted November 28, 2012 by corbet]
| From: |
| Linus Torvalds <torvalds-AT-linux-foundation.org> |
| To: |
| Johannes Weiner <hannes-AT-cmpxchg.org> |
| Subject: |
| Re: kswapd craziness in 3.7 |
| Date: |
| Tue, 27 Nov 2012 15:19:38 -0800 |
| Message-ID: |
| <CA+55aFyrNRF8nWyozDPi4O1bdjzO189YAgMukyhTOZ9fwKqOpA@mail.gmail.com> |
| Cc: |
| Rik van Riel <riel-AT-redhat.com>,
Andrew Morton <akpm-AT-linux-foundation.org>,
Mel Gorman <mgorman-AT-suse.de>,
George Spelvin <linux-AT-horizon.com>,
Johannes Hirte <johannes.hirte-AT-fem.tu-ilmenau.de>,
Tomas Racek <tracek-AT-redhat.com>, Jan Kara <jack-AT-suse.cz>,
Dave Hansen <dave-AT-linux.vnet.ibm.com>,
Josh Boyer <jwboyer-AT-gmail.com>,
Valdis Kletnieks <Valdis.Kletnieks-AT-vt.edu>,
Jiri Slaby <jslaby-AT-suse.cz>,
Thorsten Leemhuis <fedora-AT-leemhuis.info>,
Zdenek Kabelac <zkabelac-AT-redhat.com>,
Bruno Wolff III <bruno-AT-wolff.to>,
linux-mm <linux-mm-AT-kvack.org>,
Linux Kernel Mailing List <linux-kernel-AT-vger.kernel.org> |
| Archive‑link: | |
Article |
On Tue, Nov 27, 2012 at 2:26 PM, Johannes Weiner <hannes@cmpxchg.org> wrote:
> On Tue, Nov 27, 2012 at 05:02:36PM -0500, Rik van Riel wrote:
>>
>> Kswapd going crazy is certainly a large part of the problem.
>>
>> However, that leaves the issue of page_alloc.c waking up
>> kswapd when the system is not actually low on memory.
>>
>> Instead, kswapd is woken up because memory compaction failed,
>> potentially even due to lock contention during compaction!
>>
>> Ideally the allocation code would only wake up kswapd if
>> memory needs to be freed, or in order for kswapd to do
>> memory compaction (so the allocator does not have to).
>
> Maybe I missed something, but shouldn't this be solved with my patch?
Ok, guys. Cage fight!
The rules are simple: two men enter, one man leaves.
And the one who comes out gets to explain to me which patch(es) I
should apply, and which I should revert, if any.
My current guess is that I should apply the one Johannes just sent
("mm: vmscan: fix kswapd endless loop on higher order allocation")
after having added the cc to stable to it, and then revert the recent
revert (commit 82b212f40059).
But I await the Thunderdome. <Cue Tina Turner "We Don't Need Another Hero">
Linus
--
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/
