linux-kernel - Re: [RFC][PATCH] page reclaim throttle take2

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.1.00.0802270045400.31372@chino.kir.corp.google.com>
Date:	Wed, 27 Feb 2008 00:47:17 -0800 (PST)
From:	David Rientjes <rientjes@...gle.com>
To:	Balbir Singh <balbir@...ux.vnet.ibm.com>
cc:	KOSAKI Motohiro <kosaki.motohiro@...fujitsu.com>,
	KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com>,
	Peter Zijlstra <a.p.zijlstra@...llo.nl>,
	linux-kernel@...r.kernel.org, linux-mm@...ck.org,
	Rik van Riel <riel@...hat.com>,
	Lee Schermerhorn <Lee.Schermerhorn@...com>,
	Nick Piggin <npiggin@...e.de>
Subject: Re: [RFC][PATCH] page reclaim throttle take2

On Wed, 27 Feb 2008, Balbir Singh wrote:

> Let's forget node hotplug for the moment, but what if someone
> 
> 1. Changes the machine configuration and adds more nodes, do we expect the
> kernel to be recompiled? Or is it easier to update /etc/sysctl.conf?
> 2. Uses fake NUMA nodes and increases/decreases the number of nodes across
> reboots. Should the kernel be recompiled?
> 

That is why the proposal was made to make this a static configuration 
option, such as CONFIG_NUM_RECLAIM_THREADS_PER_NODE, that will handle both 
situations.

> I am afraid it doesn't. Consider as you scale number of CPU's with the same
> amount of memory, we'll end up making the reclaim problem worse.
> 

The benchmark that have been posted suggest that memory locality is more 
important than lock contention, as I've already mentioned.

		David
--
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/