linux-kernel - [.32-rc3] scheduler: iwlagn consistently high in "waiting for CPU"

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-next>] [day] [month] [year] [list]

Message-Id: <200910051500.55875.elendil@planet.nl>
Date:	Mon, 5 Oct 2009 15:00:54 +0200
From:	Frans Pop <elendil@...net.nl>
To:	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>
Cc:	Ingo Molnar <mingo@...e.hu>, Peter Zijlstra <peterz@...radead.org>,
	linux-wireless@...r.kernel.org
Subject: [.32-rc3] scheduler: iwlagn consistently high in "waiting for CPU"

With .32-rc3 I'm getting occasional skips from amarok while playing music 
from an NFS share (3 today so far), something I've not had in a long time.

The reason looks to be that latencytop consistently shows 'iwlagn' as the 
top affected process with "Scheduler: waiting for CPU".
Values of 100-140 ms occur frequently, but I've also seen higher values 
(180, 207). I don't remember seeing iwlagn high in the list before, but I 
have not checked earlier kernels yet.

Added to that 'phy0' also frequently shows high with values of 25-75 ms.

The system is otherwise essentially idle. Other processes typically show a 
latency < 5 ms.

System: HP 2510p notebook, x86_64, Core2 Duo, Debian stable

Cheers,
FJP
--
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/