linux-kernel - Re: nice and hyperthreading on atom

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:	Sat, 6 Sep 2008 09:42:48 -0700
From:	Arjan van de Ven <arjan@...radead.org>
To:	"Phil Endecott" <phil_wueww_endecott@...zphil.org>
Cc:	"Linux Kernel Mailing List" <linux-kernel@...r.kernel.org>
Subject: Re: nice and hyperthreading on atom

On Sat, 06 Sep 2008 16:43:31 +0100
"Phil Endecott" <phil_wueww_endecott@...zphil.org> wrote:

> Dear Experts,
> 
> I have an ASUS Eee with an Atom processor, which has hyperthreading 
> enabled.  If I have two processes, one nice and the other normal,
> they each get 50% of the CPU time.  Of course this is what you'd
> expect if the scheduler didn't understand that the two virtual
> processors are not really independent.  I'd like to fix it.
> 

but you cannot imfluence the cpu's scheduling of the instructions.

As an OS one COULD decide to just not schedule the nice task at all,
but then, especially on atom where HT has a high efficiency, your cpu
is mostly idle ...

-- 
If you want to reach me at my work email, use arjan@...ux.intel.com
For development, discussion and tips for power savings, 
visit http://www.lesswatts.org
--
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/