linux-kernel - RCU related performance regression in 3.3

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 for Android: free password hash cracker in your pocket

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:	Wed, 4 Apr 2012 11:27:27 -0400
From:	Josh Boyer <jwboyer@...hat.com>
To:	paulmck@...ux.vnet.ibm.com
Cc:	linux-kernel@...r.kernel.org, kernel-team@...oraproject.org
Subject: RCU related performance regression in 3.3

Hi Paul,

We've had a few reports of some boot slowdowns with the 3.3 rebase we
did in Fedora 16.  One of our users volunteered to bisect a vanilla
kernel and wound up at "rcu: Permit dyntick-idle with callbacks pending
(commit 7cb924990)".  You can find more details in the bug [1], but it's
been reported on both physical hardware and in virtual machines.

Have you seen anything like this in your testing?  Given the user used a
vanilla 3.3 kernel, I'm wondering if there is a targetted fix that might
be backported.  If so, it would be good to get that headed to the 3.3.y
stable tree.

josh

[1] https://bugzilla.redhat.com/show_bug.cgi?id=806548
--
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/