From owner-freebsd-stable@FreeBSD.ORG Sat Jan 1 19:09:33 2011 Return-Path: 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 A9A0E106564A; Sat, 1 Jan 2011 19:09:33 +0000 (UTC) (envelope-from artemb@gmail.com) Received: from mail-ww0-f42.google.com (mail-ww0-f42.google.com [74.125.82.42]) by mx1.freebsd.org (Postfix) with ESMTP id DFD5F8FC15; Sat, 1 Jan 2011 19:09:32 +0000 (UTC) Received: by wwi17 with SMTP id 17so12843527wwi.1 for ; Sat, 01 Jan 2011 11:09:31 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:sender:received :in-reply-to:references:date:x-google-sender-auth:message-id:subject :from:to:cc:content-type; bh=K8i/jWVzO1r5x2IgYWNKM5hWXmxpDl7KRJTmSQMIPhM=; b=OL7gJgtgYQnCt86aUuCVQ4fUZl+lSzH1L8u7PwIAHk3iItaFDHadf2epnbnKsuqusH mzILAjLp9m5msX1nanlDXanuKxfBVdDat/MBwJvgc3UGux4kLE9XjJ6q9rCGlW/b0auN M8zQ4GZNUh20G027MDsB/4QC84y5yEBlbYofQ= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:cc:content-type; b=iJC3ei/nOpKzH6Dwo7T9P8uzyzTU58iPhsnuSzzoBfXyBZCFXsz0MhqWFFoaMFv+Cf 2eAAKyDuxc7ZZ7BmujBXLPWumvkuuMBLVVyuidlRoN5yodr4jEBgCDM35YbirmdUCc93 Ad+S/SPn0YmM9AL0Or9udlFNxScS1FyZjmmVc= MIME-Version: 1.0 Received: by 10.227.137.203 with SMTP id x11mr10989261wbt.80.1293908971710; Sat, 01 Jan 2011 11:09:31 -0800 (PST) Sender: artemb@gmail.com Received: by 10.227.129.6 with HTTP; Sat, 1 Jan 2011 11:09:31 -0800 (PST) In-Reply-To: <4D1F7008.3050506@fsn.hu> References: <4D0A09AF.3040005@FreeBSD.org> <4D1F7008.3050506@fsn.hu> Date: Sat, 1 Jan 2011 11:09:31 -0800 X-Google-Sender-Auth: YVPJG4s-m-QcEYPXj1NRZyvNvRg Message-ID: From: Artem Belevich To: Attila Nagy Content-Type: text/plain; charset=ISO-8859-1 Cc: freebsd-fs@freebsd.org, freebsd-stable@freebsd.org, Martin Matuska Subject: Re: New ZFSv28 patchset for 8-STABLE X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 01 Jan 2011 19:09:33 -0000 On Sat, Jan 1, 2011 at 10:18 AM, Attila Nagy wrote: > What I see: > - increased CPU load > - decreased L2 ARC hit rate, decreased SSD (ad[46]), therefore increased > hard disk load (IOPS graph) > ... > Any ideas on what could cause these? I haven't upgraded the pool version and > nothing was changed in the pool or in the file system. The fact that L2 ARC is full does not mean that it contains the right data. Initial L2ARC warm up happens at a much higher rate than the rate L2ARC is updated after it's been filled initially. Even accelerated warm-up took almost a day in your case. In order for L2ARC to warm up properly you may have to wait quite a bit longer. My guess is that it should slowly improve over the next few days as data goes through L2ARC and those bits that are hit more often take residence there. The larger your data set, the longer it will take for L2ARC to catch the right data. Do you have similar graphs from pre-patch system just after reboot? I suspect that it may show similarly abysmal L2ARC hit rates initially, too. --Artem