From owner-freebsd-performance@FreeBSD.ORG Fri Nov 9 12:33:38 2012 Return-Path: Delivered-To: freebsd-performance@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 721472CA for ; Fri, 9 Nov 2012 12:33:38 +0000 (UTC) (envelope-from turbolad995@yahoo.co.uk) Received: from nm14-vm0.bullet.mail.ird.yahoo.com (nm14-vm0.bullet.mail.ird.yahoo.com [77.238.189.193]) by mx1.freebsd.org (Postfix) with ESMTP id 954308FC0C for ; Fri, 9 Nov 2012 12:33:37 +0000 (UTC) Received: from [77.238.189.233] by nm14.bullet.mail.ird.yahoo.com with NNFMP; 09 Nov 2012 12:33:36 -0000 Received: from [217.146.188.224] by tm14.bullet.mail.ird.yahoo.com with NNFMP; 09 Nov 2012 12:33:35 -0000 Received: from [127.0.0.1] by smtp104.mail.ird.yahoo.com with NNFMP; 09 Nov 2012 12:33:35 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yahoo.co.uk; s=s1024; t=1352464415; bh=KOyb0zh+ePIhdtwY9hZhWfKBLEsZJ9gbGTwyg6KKIyw=; h=X-Yahoo-Newman-Id:X-Yahoo-Newman-Property:X-YMail-OSG:X-Yahoo-SMTP:Received:Message-ID:Date:From:User-Agent:MIME-Version:To:Subject:Content-Type:Content-Transfer-Encoding; b=v4iRC4cnFe2lXdpZVX88z7vPVeMKVA70L9LXWdLcjCgpopiVXiaAiFca96GkNnY4N+KLorlcwuPopeag5UezmRadhdGrvgiPxqD8t40oanpRiKkUrttcFOr2grCJ2te/J0gywKrw5KZXX9xtDEaK67BGyujRpsoO01DNt+soPqg= X-Yahoo-Newman-Id: 837167.77897.bm@smtp104.mail.ird.yahoo.com X-Yahoo-Newman-Property: ymail-3 X-YMail-OSG: 2iLQdKIVM1l0uOmSRhWxSCrT_axi.HM7nt3NmW33pKPA_Hi 0Nd5hhDJNdH5LC_Cr2JelvQZb9W1TWnWTm5Oblo3l6yDy4WUJH2hhf9U4GOF poYqEQq9PCHqqZF41FNmuY7yUXPxD8yYwqOOatdN3R92pUzMILwsUphVW1Cs xyy5X00PPzmVWGqO3ZX5ovqw1WXAOoc4yzn6BK.KgdvaLYhlrCry4l6yVsW5 r6phAP146Mw6VkJ9Xs6dvCe9rWghiqsGNkF55NBgP3iC5q15c8QiQ61vPFjJ LRO7v_KbJfXnitF3M9fai9_9r28E0ac_Gp0u8eLmC.jQM9G.C4gpx3z8PpR9 2o6W26J7tlpZaynSAsqOhnjyYdboBc1b0QpWp12Ydzpeee3a8cvKOSLtWmDz 4TI4hP6BM1YUUtPMmk8IFo91Yo1LO05ZDr81azZra72lBcurm62Nl.9pS_Ij 3d_rdFzBlp7kQ7s8KODYf8i1U4r_rRSFjGZVrCQhqtP6j48YrEvuMUuB0_VP SM1Nke6JwMwp7QroAYQ-- X-Yahoo-SMTP: WcC0Nl2swBAf69I64R_Ejre9DIAnIdrO Received: from [192.168.0.2] (turbolad995@213.106.180.190 with plain) by smtp104.mail.ird.yahoo.com with SMTP; 09 Nov 2012 04:33:35 -0800 PST Message-ID: <509CF81F.7090803@yahoo.co.uk> Date: Fri, 09 Nov 2012 12:33:35 +0000 From: David User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:16.0) Gecko/20121028 Thunderbird/16.0.2 MIME-Version: 1.0 To: freebsd-performance@freebsd.org Subject: Compressed RAM disk swap space Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-BeenThere: freebsd-performance@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Performance/tuning List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 09 Nov 2012 12:33:38 -0000 Hi, I have tried something which actually boosts performance: a compressed RAM disk used as swap space. As an end user, I do a lot of testing on PC-BSD and Ubuntu. It was suggested in the PC-BSD forums I put my idea in one of these mailing lists. The compressed RAM disk I tested is called "zRam" and I use it on Ubuntu. It makes a noticeable difference on older computers e.g. 1GB of RAM. Would the same feature work in FreeBSD and PC-BSD? I use PC-BSD. The zRam feature really *does* boost performance. As an end-user, I don't know exactly how it works; I just installed it from the "Software Centre" in Ubuntu and enjoy the performance boost and I have noticed the hard disk is not constantly in use, compared to not using zRam. You can see my original posting in the PC-BSD forums: http://forums.pcbsd.org/showthread.php?t=18557 Hope this idea is considered. :) From owner-freebsd-performance@FreeBSD.ORG Fri Nov 9 13:37:49 2012 Return-Path: Delivered-To: freebsd-performance@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 8187F4AA for ; Fri, 9 Nov 2012 13:37:49 +0000 (UTC) (envelope-from ap@bnc.net) Received: from mailomat.net (mailomat.net [81.20.89.254]) by mx1.freebsd.org (Postfix) with ESMTP id 0F18E8FC08 for ; Fri, 9 Nov 2012 13:37:48 +0000 (UTC) X-Mailomat-SpamCatcher-Score: 2 [X] X-Mailomat-Junk-Score: 0 [] X-Mailomat-Cloudmark-Score: 0 [] Received: from [194.39.192.125] (account bnc-mail@mailrelay.mailomat.net HELO bnc.net) by mailomat.net (CommuniGate Pro SMTP 5.4.5) with ESMTPSA id 59002872; Fri, 09 Nov 2012 14:37:47 +0100 X-Junk-Score: 2 [X] X-SpamCatcher-Score: 2 [X] Received: from [192.168.200.191] (account ap@bnc.net HELO [192.168.200.191]) by bnc.net (CommuniGate Pro SMTP 6.0c1) with ESMTPSA id 6870459; Fri, 09 Nov 2012 14:40:37 +0100 Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 6.1 \(1498\)) Subject: Re: Compressed RAM disk swap space From: Achim Patzner In-Reply-To: <509CF81F.7090803@yahoo.co.uk> Date: Fri, 9 Nov 2012 14:37:46 +0100 Content-Transfer-Encoding: quoted-printable Message-Id: References: <509CF81F.7090803@yahoo.co.uk> To: David X-Mailer: Apple Mail (2.1498) Cc: freebsd-performance@freebsd.org X-BeenThere: freebsd-performance@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Performance/tuning List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 09 Nov 2012 13:37:49 -0000 Am 09.11.2012 um 13:33 schrieb David : > Hi, I have tried something which actually boosts performance It doesn't; it just moves the load from one limited resource (RAM) to = another one (CPU cycles), adding its own overhead on the way. It just = means that your machine got too large an engine for your tires. Save on = CPU power and get more RAM next time. > : a compressed RAM disk used as swap space. It nearly sounds as good as "hey, we've got virtual memory, let's = generate an incredibly large RAM disk". To me it sounds like investing = into sovereign debt of your home country and paying your interest rate = with your own increased taxes. Why swap into RAM if your process could = use it as well? About the cost of compression: This idea was already annoying decades = ago (doesn't anyone remember those "RAM extenders" for MS-DOS that gave = you "more RAM than your computer contains"?) when software suddenly got = inexplicably slow (until you found the driver chewing on its own tail by = trying to decompress itself) and was one of the reasons I moved to SCO = and BSD/386. Achim