linux-kernel - Re: [RFC] Cpu-hotplug: Using the Process Freezer (try2)

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:	Wed, 4 Apr 2007 13:49:01 +0200
From:	Ingo Molnar <mingo@...e.hu>
To:	Gautham R Shenoy <ego@...ibm.com>
Cc:	Srivatsa Vaddagiri <vatsa@...ibm.com>, akpm@...ux-foundation.org,
	paulmck@...ibm.com, torvalds@...ux-foundation.org,
	linux-kernel@...r.kernel.org, Oleg Nesterov <oleg@...sign.ru>,
	"Rafael J. Wysocki" <rjw@...k.pl>, dipankar@...ibm.com,
	dino@...ibm.com, masami.hiramatsu.pt@...achi.com
Subject: Re: [RFC] Cpu-hotplug: Using the Process Freezer (try2)


* Gautham R Shenoy <ego@...ibm.com> wrote:

> On Wed, Apr 04, 2007 at 12:04:31PM +0200, Ingo Molnar wrote:
> > 
> > yeah, i think you are right - and the TASK_UNINTERRUPTIBLE thing is 
> > not only quite complex, it also breaks the symmetry of freezer use 
> > (sw-suspend obviously cannot freeze uninterruptible tasks). We 
> > should watch whether the current latency of freezing is good enough 
> > in practice.
> 
> Ok. Do you have any specific tests in mind which I can run and post 
> the numbers?
> 
> As of now, I've been stressing the system with (kernbench + ondemand 
> governor) and timing the hotplug operation.

i suspect a fork-intensive application like kernbench should be close to 
the worst-case already. A more IO-intensive workload would maximize the 
uninterruptible-sleep latencies perhaps?

	Ingo
-
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/