linux-kernel - [Question] : tie a task to a cluster when it shares memory resources

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>] [day] [month] [year] [list]

Date:	Tue, 29 Oct 2013 10:32:33 -0700
From:	Daniel Lezcano <daniel.lezcano@...aro.org>
To:	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	Peter Zijlstra <a.p.zijlstra@...llo.nl>
CC:	Ingo Molnar <mingo@...nel.org>
Subject: [Question] : tie a task to a cluster when it shares memory resources

Hi all,

I am not expert on the NUMA area and the scheduler but I was wondering 
the following:

On numa a process can define a memory policy to optimize access because 
remote memory access is suboptimal.

On a multicluster (aka multipackage), eg. Bi-Xeon 4 cores, the scheduler 
load balancing can spawn/balance a task to the second cluster even if 
the task is resulting from a fork or a pthread_create. If I am correct 
that could impact the performances due to L2 cache misses, no ?

Won't it be more efficient to tie a task to a cluster when it shares 
memory resources with another task on the same cluster ? and when the 
task does 'exec', this constraint is removed.

Thanks
-- Daniel

-- 
  <http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs

Follow Linaro:  <http://www.facebook.com/pages/Linaro> Facebook |
<http://twitter.com/#!/linaroorg> Twitter |
<http://www.linaro.org/linaro-blog/> Blog

--
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/