From: Minchan Kim <minchan.kim@gmail.com>
To: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: LKML <linux-kernel@vger.kernel.org>,
linux-mm <linux-mm@kvack.org>,
Andrew Morton <akpm@linux-foundation.org>,
Balbir Singh <balbir@linux.vnet.ibm.com>,
KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>,
Rik van Riel <riel@redhat.com>
Subject: Re: [PATCH 2/3][v2] vmstat: add anon_scan_ratio field to zoneinfo
Date: Sat, 16 Jan 2010 02:23:16 +0900 [thread overview]
Message-ID: <28c262361001150923l138f6805t22546887bf81b283@mail.gmail.com> (raw)
In-Reply-To: <20100114141735.672B.A69D9226@jp.fujitsu.com>
Hi, KOSAKI.
On Thu, Jan 14, 2010 at 2:18 PM, KOSAKI Motohiro
<kosaki.motohiro@jp.fujitsu.com> wrote:
>> > Well. zone->lock and zone->lru_lock should be not taked at the same time.
>>
>> I looked over the code since I am out of office.
>> I can't find any locking problem zone->lock and zone->lru_lock.
>> Do you know any locking order problem?
>> Could you explain it with call graph if you don't mind?
>>
>> I am out of office by tomorrow so I can't reply quickly.
>> Sorry for late reponse.
>
> This is not lock order issue. both zone->lock and zone->lru_lock are
> hotpath lock. then, same tame grabbing might cause performance impact.
Sorry for late response.
Your patch makes get_anon_scan_ratio of zoneinfo stale.
What you said about performance impact is effective when VM pressure high.
I think stale data is all right normally.
But when VM pressure is high and we want to see the information in zoneinfo(
this case is what you said), stale data is not a good, I think.
If it's not a strong argue, I want to use old get_scan_ratio
in get_anon_scan_ratio.
--
Kind regards,
Minchan Kim
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
next prev parent reply other threads:[~2010-01-15 17:23 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-01-13 8:19 [PATCH 1/3] vmscan: get_scan_ratio cleanup KOSAKI Motohiro
2010-01-13 8:21 ` [PATCH 2/3][v2] vmstat: add anon_scan_ratio field to zoneinfo KOSAKI Motohiro
2010-01-13 10:31 ` Minchan Kim
2010-01-13 23:50 ` KOSAKI Motohiro
2010-01-14 5:12 ` Minchan Kim
2010-01-14 5:18 ` KOSAKI Motohiro
2010-01-15 17:23 ` Minchan Kim [this message]
2010-01-18 1:04 ` KOSAKI Motohiro
2010-01-18 1:47 ` Minchan Kim
2010-01-18 1:54 ` KOSAKI Motohiro
2010-01-18 2:10 ` Minchan Kim
2010-01-18 2:14 ` KOSAKI Motohiro
2010-01-18 2:16 ` Rik van Riel
2010-01-18 2:24 ` KOSAKI Motohiro
2010-01-18 2:25 ` Minchan Kim
2010-01-13 8:22 ` [PATCH 3/3] [v2] memcg: add anon_scan_ratio to memory.stat file KOSAKI Motohiro
2010-01-13 8:24 ` KAMEZAWA Hiroyuki
2010-01-13 9:08 ` Balbir Singh
2010-01-13 9:54 ` [PATCH 1/3] vmscan: get_scan_ratio cleanup Minchan Kim
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=28c262361001150923l138f6805t22546887bf81b283@mail.gmail.com \
--to=minchan.kim@gmail.com \
--cc=akpm@linux-foundation.org \
--cc=balbir@linux.vnet.ibm.com \
--cc=kamezawa.hiroyu@jp.fujitsu.com \
--cc=kosaki.motohiro@jp.fujitsu.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=riel@redhat.com \
/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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox