linux-kernel - Re: [patch 00/20] VM pageout scalability improvements

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]

Date:	Sun, 23 Dec 2007 01:57:32 +0530
From:	Balbir Singh <balbir@...ux.vnet.ibm.com>
To:	Rik van Riel <riel@...hat.com>
CC:	linux-mm@...ck.org, linux-kernel@...r.kernel.org,
	lee.shermerhorn@...com
Subject: Re: [patch 00/20] VM pageout scalability improvements

Rik van Riel wrote:
> On large memory systems, the VM can spend way too much time scanning
> through pages that it cannot (or should not) evict from memory. Not
> only does it use up CPU time, but it also provokes lock contention
> and can leave large systems under memory presure in a catatonic state.
> 

Hi, Rik,

I remember you mentioning that by large memory systems you mean systems
with at-least 128GB, does this definition still hold?

> This patch series improves VM scalability by:
> 
> 1) making the locking a little more scalable
> 
> 2) putting filesystem backed, swap backed and non-reclaimable pages
>    onto their own LRUs, so the system only scans the pages that it
>    can/should evict from memory
> 
> 3) switching to SEQ replacement for the anonymous LRUs, so the
>    number of pages that need to be scanned when the system
>    starts swapping is bound to a reasonable number
> 
> The noreclaim patches come verbatim from Lee Schermerhorn and
> Nick Piggin.  I have not taken a detailed look at them yet and
> all I have done is fix the rejects against the latest -mm kernel.
> 

Is there a consolidate patch available, it makes it easier to test.

> I am posting this series now because I would like to get more
> feedback, while I am studying and improving the noreclaim patches
> myself.
> 

What kind of tests show the problem? I'll try and review and test the code.

-- 
	Warm Regards,
	Balbir Singh
	Linux Technology Center
	IBM, ISTL
--
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/