linux-kernel - Re: [PATCH 3/3] Provide control over unmapped pages (v4)

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: <alpine.DEB.2.00.1101280917570.1194@router.home>
Date:	Fri, 28 Jan 2011 09:20:02 -0600 (CST)
From:	Christoph Lameter <cl@...ux.com>
To:	KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com>
cc:	Minchan Kim <minchan.kim@...il.com>, balbir@...ux.vnet.ibm.com,
	linux-mm@...ck.org, akpm@...ux-foundation.org, npiggin@...nel.dk,
	kvm@...r.kernel.org, linux-kernel@...r.kernel.org,
	kosaki.motohiro@...fujitsu.com
Subject: Re: [PATCH 3/3] Provide control over unmapped pages (v4)

On Fri, 28 Jan 2011, KAMEZAWA Hiroyuki wrote:

> > > I see it as a tradeoff of when to check? add_to_page_cache or when we
> > > are want more free memory (due to allocation). It is OK to wakeup
> > > kswapd while allocating memory, somehow for this purpose (global page
> > > cache), add_to_page_cache or add_to_page_cache_locked does not seem
> > > the right place to hook into. I'd be open to comments/suggestions
> > > though from others as well.
>
> I don't like add hook here.
> AND I don't want to run kswapd because 'kswapd' has been a sign as
> there are memory shortage. (reusing code is ok.)
>
> How about adding new daemon ? Recently, khugepaged, ksmd works for
> managing memory. Adding one more daemon for special purpose is not
> very bad, I think. Then, you can do
>  - wake up without hook
>  - throttle its work.
>  - balance the whole system rather than zone.
>    I think per-node balance is enough...


I think we already have enough kernel daemons floating around. They are
multiplying in an amazing way. What would be useful is to map all
the memory management background stuff into a process. May call this memd
instead? Perhaps we can fold khugepaged into kswapd as well etc.
--
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/