From owner-freebsd-hackers@FreeBSD.ORG Tue Aug 24 02:28:24 2010 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id B3DAC106566B; Tue, 24 Aug 2010 02:28:24 +0000 (UTC) (envelope-from jhellenthal@gmail.com) Received: from mail-qw0-f54.google.com (mail-qw0-f54.google.com [209.85.216.54]) by mx1.freebsd.org (Postfix) with ESMTP id 2A2038FC0C; Tue, 24 Aug 2010 02:28:23 +0000 (UTC) Received: by qwg5 with SMTP id 5so6357727qwg.13 for ; Mon, 23 Aug 2010 19:28:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:sender:message-id:date:from :user-agent:mime-version:to:cc:subject:references:in-reply-to :x-enigmail-version:content-type:content-transfer-encoding; bh=4fqi2BKYIFEmvU/VaYL9GXnmLV0JV5sO/hxD8y23fXs=; b=M2Qj8kXme19LMVKALA+bjWIEeYNPKCijeayda53m1IusGhUGVRQBvU8s3v4PumuTX+ 72+f6C+h8lxI7s/yqsPaI3+NTn30gMn0YWW9fH48uTnSzOEnRAOnEDxb+waQ9pOFV3f4 1nxIonIY6FZMW6PTu5hzj325/yyWVW6sIYuAo= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=sender:message-id:date:from:user-agent:mime-version:to:cc:subject :references:in-reply-to:x-enigmail-version:content-type :content-transfer-encoding; b=CDhllPG/5p5AXC7g4Ag5NBQmenfeMYIZEVUIt66q69RkzsL2d3sMYWeHscJv9u6x68 5f9djOhJMH0rySgHs5bEBShxAdCjQ5U5tnU4sK+qdHySfJUgHyrg1uFrUCvJTb0grPy7 hPMPTIj3/pWmqq12DFOojVtP0EV3sualPRk4A= Received: by 10.229.222.6 with SMTP id ie6mr4311550qcb.28.1282616903208; Mon, 23 Aug 2010 19:28:23 -0700 (PDT) Received: from centel.dataix.local (adsl-99-190-84-182.dsl.klmzmi.sbcglobal.net [99.190.84.182]) by mx.google.com with ESMTPS id t4sm7901199qcs.40.2010.08.23.19.28.21 (version=SSLv3 cipher=RC4-MD5); Mon, 23 Aug 2010 19:28:22 -0700 (PDT) Sender: "J. Hellenthal" Message-ID: <4C732E44.50702@DataIX.net> Date: Mon, 23 Aug 2010 22:28:20 -0400 From: jhell User-Agent: Mozilla/5.0 (X11; U; FreeBSD i386; en-US; rv:1.9.2.8) Gecko/20100806 Lightning/1.0b1 Thunderbird MIME-Version: 1.0 To: Artem Belevich References: <4C719AB9.9020006@freebsd.org> <4C721161.40403@freebsd.org> <4C72DD1A.9070204@DataIX.net> <4C72DDC3.1000006@DataIX.net> In-Reply-To: X-Enigmail-Version: 1.1.2 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: freebsd-hackers@freebsd.org, zfs-devel@freebsd.org, Andriy Gapon Subject: Re: ZFS arc_reclaim_needed: better cooperation with pagedaemon X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 24 Aug 2010 02:28:24 -0000 On 08/23/2010 22:10, Artem Belevich wrote: > First prepare the data. > * You'll need some files totalling around the amount of physical > memory on your box. Multiple copies of /usr/src should do the trick. > * Place one copy on UFS filesystem and another on ZFS > > Experiment #1: > * Prime ARC by tarring dataset on ZFS into /dev/null. > * Now tar both datasets in parallel with output to /dev/null > > Previously you would end up with ARC size shrinking down to arc_min. > What I hope to see after the patch is that inactive memory and ARC > reach some sort of equilibrium with neither monopolizing all available > memory. > > #Experiment #2: > If equilibrium is reached, try running some application that would > allocate and use about 1/2 of your physical memory. > Something like that perl one-liner used to cause memory shortage, only > a bit less drastic. > perl -e '$x="x"x1_000_000_000'; # this should allocate about 2GB. > Tune the number to suit your system. > > Again, in the past ARC would be the one feeing up the memory. Let's > see if inactive list gives up some, too. Alright I should be able to have something together with the output of this by the 25th with my current workload being the ultimate determining factor. PBS, Regards, -- jhell,v