linux-kernel - Re: [PATCH] mm: remove zone->prev

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20090211195252.C3BD.KOSAKI.MOTOHIRO@jp.fujitsu.com>
Date:	Wed, 11 Feb 2009 20:06:46 +0900 (JST)
From:	KOSAKI Motohiro <kosaki.motohiro@...fujitsu.com>
To:	Andrew Morton <akpm@...ux-foundation.org>
Cc:	kosaki.motohiro@...fujitsu.com,
	MinChan Kim <minchan.kim@...il.com>,
	kamezawa.hiroyu@...fujitsu.com, linux-kernel@...r.kernel.org,
	linux-mm@...ck.org, riel@...hat.com
Subject: Re: [PATCH] mm: remove zone->prev_prioriy

> On Tue, 10 Feb 2009 19:57:01 +0900
> MinChan Kim <minchan.kim@...il.com> wrote:
> 
> > As you know, prev_priority is used as a measure of how much stress page reclaim.
> > But now we doesn't need it due to split-lru's way.
> > 
> > I think it would be better to remain why prev_priority isn't needed any more
> > and how split-lru can replace prev_priority's role in changelog.
> > 
> > In future, it help mm newbies understand change history, I think.
> 
> Yes, I'd be fascinated to see that explanation.
> 
> In http://groups.google.pn/group/linux.kernel/browse_thread/thread/fea9c9a0b43162a1
> it was asserted that we intend to use prev_priority again in the future.
> 
> We discussed this back in November:
> http://lkml.indiana.edu/hypermail/linux/kernel/0811.2/index.html#00001
> 
> And I think that I still think that the VM got worse due to its (new)
> failure to track previous state.  IIRC, the response to that concern
> was quite similar to handwavy waffling.

Yes.
I still think it's valuable code.
I think, In theory, VM sould take parallel reclaim bonus.

However, recently, KAMEZAWA-san reported memcg prev_priority code are
busted due to hierarchical-memory-reclaim and he dislike maintain 
unused function.

http://marc.info/?l=linux-mm&m=123258289017433&w=2


and, at that time I can't show good example workload of parallel reclaim bonus
effective.
Therefore I agreed to drop this and insert it again at re-using time ;-)



--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/