From owner-freebsd-stable@FreeBSD.ORG  Tue Oct 11 09:46:15 2011
Return-Path: <owner-freebsd-stable@FreeBSD.ORG>
Delivered-To: freebsd-stable@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id 98B4B106564A;
	Tue, 11 Oct 2011 09:46:15 +0000 (UTC)
	(envelope-from prvs=1265807bed=killing@multiplay.co.uk)
Received: from mail1.multiplay.co.uk (mail1.multiplay.co.uk [85.236.96.23])
	by mx1.freebsd.org (Postfix) with ESMTP id D947E8FC19;
	Tue, 11 Oct 2011 09:46:14 +0000 (UTC)
X-MDAV-Processed: mail1.multiplay.co.uk, Tue, 11 Oct 2011 10:34:02 +0100
X-Spam-Processed: mail1.multiplay.co.uk, Tue, 11 Oct 2011 10:34:02 +0100
X-Spam-Checker-Version: SpamAssassin 3.2.5 (2008-06-10) on
	mail1.multiplay.co.uk
X-Spam-Level: 
X-Spam-Status: No, score=-5.0 required=6.0 tests=USER_IN_WHITELIST
	shortcircuit=ham autolearn=disabled version=3.2.5
Received: from r2d2 ([188.220.16.49])
	by mail1.multiplay.co.uk (mail1.multiplay.co.uk [85.236.96.23])
	(MDaemon PRO v10.0.4) with ESMTP id md50015512102.msg;
	Tue, 11 Oct 2011 10:34:01 +0100
X-MDRemoteIP: 188.220.16.49
X-Return-Path: prvs=1265807bed=killing@multiplay.co.uk
X-Envelope-From: killing@multiplay.co.uk
Message-ID: <852472071289497FA806928D0B41D0FE@multiplay.co.uk>
From: "Steven Hartland" <killing@multiplay.co.uk>
To: =?iso-8859-1?Q?Micka=EBl_Maillot?= <mickael.maillot@gmail.com>,
	"Christer Solskogen" <christer.solskogen@gmail.com>
References: <AANLkTinzwyhABYxzWknzRFzLCbcDSd3BU2kQ5tX_SSk-@mail.gmail.com><20101116003029.GC79816@numachi.com><AANLkTinfTgXzf7t3PtO2VAef7NSkKWc0RnGdpv=6_-Vj@mail.gmail.com><ibtqvp$bfq$1@dough.gmane.org><AANLkTi=tJ-Hf+rMqG0=tEzNV2jJW-B_7Yu_ftW4tAMqT@mail.gmail.com><20101116125431.GA90475@icarus.home.lan><AANLkTi=mAWYCnWbWbX9B9fa05iyC_pivu08v-+bOf75f@mail.gmail.com><AANLkTi=p9U6gK=Z5GyrAEzU2tDqbx+yWY=4eTZ5-0CuF@mail.gmail.com><AANLkTi=XwO0RrU9uY5CF5p+b9co1yneXX7UR2JsF55bL@mail.gmail.com><AANLkTiknP4D5aayotFQ1jFpmov9Vv50GnFdVaXXs39rL@mail.gmail.com>
	<AANLkTikjd5CgcC3TEhLYuBXGukP0mUCyHtY-FwfYqs1K@mail.gmail.com>
Date: Tue, 11 Oct 2011 10:34:04 +0100
MIME-Version: 1.0
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
	reply-type=original
Content-Transfer-Encoding: 8bit
X-Priority: 3
X-MSMail-Priority: Normal
X-Mailer: Microsoft Outlook Express 6.00.2900.5931
X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.6109
Cc: freebsd-stable@freebsd.org, Ivan Voras <ivoras@freebsd.org>,
	Jeremy Chadwick <freebsd@jdc.parodius.com>
Subject: Re: "High" cpu usage when using ZFS cache device
X-BeenThere: freebsd-stable@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: Production branch of FreeBSD source code <freebsd-stable.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-stable>, 
	<mailto:freebsd-stable-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-stable>
List-Post: <mailto:freebsd-stable@freebsd.org>
List-Help: <mailto:freebsd-stable-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-stable>,
	<mailto:freebsd-stable-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Tue, 11 Oct 2011 09:46:15 -0000

----- Original Message ----- 
From: "Mickaël Maillot" <mickael.maillot@gmail.com>


> same problem here after ~ 30 days with a production server and 2 SSD Intel
> X25M as L2.
> so we update and reboot the 8-STABLE server every month.

Old thread but also seeing this on 8.2-RELEASE so looks like this
may still be an issue.

In our case this machine was running mysql with 2 x 60GB cache
SSD's. I checked for usage when the machine was idle just before
reboot to fix and the l2arc thread was still using 100% of a core
even with no disk access happening.

Was a PR ever raised for this?

    Regards
    Steve 


================================================
This e.mail is private and confidential between Multiplay (UK) Ltd. and the person or entity to whom it is addressed. In the event of misdirection, the recipient is prohibited from using, copying, printing or otherwise disseminating it or any information contained in it. 

In the event of misdirection, illegible or incomplete transmission please telephone +44 845 868 1337
or return the E.mail to postmaster@multiplay.co.uk.