From: Mel Gorman <mgorman@suse.de>
To: lkp@lists.01.org
Subject: Re: [mm] 795ae7a0de: pixz.throughput -9.1% regression
Date: Fri, 03 Jun 2016 10:00:46 +0100 [thread overview]
Message-ID: <20160603090046.GF2469@suse.de> (raw)
In-Reply-To: <20160602160706.GA24004@cmpxchg.org>
[-- Attachment #1: Type: text/plain, Size: 909 bytes --]
On Thu, Jun 02, 2016 at 12:07:06PM -0400, Johannes Weiner wrote:
> right before the test is running? I wonder if it's mostly filled with
> cache, and the increase in watermarks causes a higher portion of the
> anon allocs and frees to spill to the remote node, but never enough to
> enter the allocator slowpath and waking kswapd to fix it.
>
> Another suspect is the fair zone allocator, whose allocation batches
> increased as well. It shouldn't affect NUMA placement, but I wonder if
> there is a bug in there that causes false spilling to foreign nodes
> that was only bounded by the allocation batch of the foreign zone.
> Mel, does such a symptom sound familiar in any way?
>
Unfortunately not. The closest I've seen recently is bugs in the page
allocator patches that artifically enters the slow path prematurely but
that does not appear to apply here.
--
Mel Gorman
SUSE Labs
WARNING: multiple messages have this Message-ID (diff)
From: Mel Gorman <mgorman@suse.de>
To: Johannes Weiner <hannes@cmpxchg.org>
Cc: kernel test robot <xiaolong.ye@intel.com>,
Linus Torvalds <torvalds@linux-foundation.org>,
Rik van Riel <riel@redhat.com>,
David Rientjes <rientjes@google.com>,
Joonsoo Kim <iamjoonsoo.kim@lge.com>,
Andrew Morton <akpm@linux-foundation.org>,
LKML <linux-kernel@vger.kernel.org>,
lkp@01.org
Subject: Re: [lkp] [mm] 795ae7a0de: pixz.throughput -9.1% regression
Date: Fri, 3 Jun 2016 10:00:46 +0100 [thread overview]
Message-ID: <20160603090046.GF2469@suse.de> (raw)
In-Reply-To: <20160602160706.GA24004@cmpxchg.org>
On Thu, Jun 02, 2016 at 12:07:06PM -0400, Johannes Weiner wrote:
> right before the test is running? I wonder if it's mostly filled with
> cache, and the increase in watermarks causes a higher portion of the
> anon allocs and frees to spill to the remote node, but never enough to
> enter the allocator slowpath and waking kswapd to fix it.
>
> Another suspect is the fair zone allocator, whose allocation batches
> increased as well. It shouldn't affect NUMA placement, but I wonder if
> there is a bug in there that causes false spilling to foreign nodes
> that was only bounded by the allocation batch of the foreign zone.
> Mel, does such a symptom sound familiar in any way?
>
Unfortunately not. The closest I've seen recently is bugs in the page
allocator patches that artifically enters the slow path prematurely but
that does not appear to apply here.
--
Mel Gorman
SUSE Labs
next prev parent reply other threads:[~2016-06-03 9:00 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <574fd097.Frf8OIpckXVh1oaw%xiaolong.ye@intel.com>
2016-06-02 6:45 ` [mm] 795ae7a0de: pixz.throughput -9.1% regression kernel test robot
2016-06-02 6:45 ` [lkp] " kernel test robot
2016-06-02 16:07 ` Johannes Weiner
2016-06-02 16:07 ` [lkp] " Johannes Weiner
2016-06-03 2:25 ` Ye Xiaolong
2016-06-03 2:25 ` [lkp] " Ye Xiaolong
2016-06-03 9:00 ` Mel Gorman [this message]
2016-06-03 9:00 ` Mel Gorman
2016-06-03 22:21 ` Johannes Weiner
2016-06-03 22:21 ` [lkp] " Johannes Weiner
2016-06-06 8:53 ` Ye Xiaolong
2016-06-06 8:53 ` [lkp] " Ye Xiaolong
2016-06-07 4:48 ` Ye Xiaolong
2016-06-07 4:48 ` [LKP] [lkp] " Ye Xiaolong
2016-06-07 21:56 ` Johannes Weiner
2016-06-07 21:56 ` [LKP] [lkp] " Johannes Weiner
2016-06-08 5:37 ` Ye Xiaolong
2016-06-08 5:37 ` [LKP] [lkp] " Ye Xiaolong
2016-06-22 21:24 ` Johannes Weiner
2016-06-22 21:24 ` [LKP] [lkp] " Johannes Weiner
2016-06-27 14:35 ` Ye Xiaolong
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20160603090046.GF2469@suse.de \
--to=mgorman@suse.de \
--cc=lkp@lists.01.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.