From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from pigeon.gentoo.org ([208.92.234.80] helo=lists.gentoo.org) by finch.gentoo.org with esmtp (Exim 4.60) (envelope-from ) id 1QPKQL-0000Uf-LF for garchives@archives.gentoo.org; Wed, 25 May 2011 20:11:21 +0000 Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id 67CE61C350; Wed, 25 May 2011 20:08:36 +0000 (UTC) Received: from mail-ww0-f53.google.com (mail-ww0-f53.google.com [74.125.82.53]) by pigeon.gentoo.org (Postfix) with ESMTP id 1AE0E1C357 for ; Wed, 25 May 2011 20:08:35 +0000 (UTC) Received: by wwj40 with SMTP id 40so16042wwj.10 for ; Wed, 25 May 2011 13:08:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:from:to:subject:date:user-agent:references :in-reply-to:mime-version:content-type:content-transfer-encoding :message-id; bh=2cals4GelC9OoyLvvdTZ6jH83rlNJBNo1zgpZxUx+8k=; b=jkixf4Igi8AAXWyFf47TE2vbrfqA0umE96m21ve1UOx1JbWKaXoPWutkD0i7GvCVCb dgIjbvdlgsG/yqofkI8hRSiZUOl61AKnTh2M56K79Yk6eQaVrU0sU+4RQAD5xOJbWdDx 0tCRMmfGiMctG1pqCUvCNkxT8o1e7I7LX0xeM= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=from:to:subject:date:user-agent:references:in-reply-to:mime-version :content-type:content-transfer-encoding:message-id; b=BjWyC8X6VKjWUABurBWzAlBpIIeVCinPsvjy3ipP/d6e2ZAWDsjMjTJNx898TjVFkh qaVWqqyFdZLy/wM44X9s1QaARFOoZXxkG11xuYCeTso0kkF5yh6qjf9R+bJ8aibRTRC0 HPlPi9+FEWsddFjkdIWgUbh5tIKznAnxWzjko= Received: by 10.227.205.202 with SMTP id fr10mr4984062wbb.60.1306354115294; Wed, 25 May 2011 13:08:35 -0700 (PDT) Received: from nazgul.localnet (196-215-114-244.dynamic.isadsl.co.za [196.215.114.244]) by mx.google.com with ESMTPS id v58sm499713weq.12.2011.05.25.13.08.33 (version=TLSv1/SSLv3 cipher=OTHER); Wed, 25 May 2011 13:08:34 -0700 (PDT) From: Alan McKinnon To: gentoo-user@lists.gentoo.org Subject: Re: [gentoo-user] Swap performance Date: Wed, 25 May 2011 22:07:46 +0200 User-Agent: KMail/1.13.7 (Linux/2.6.38-ck-r1; KDE/4.6.3; x86_64; ; ) References: <201105251621.00659.wonko@wonkology.org> <5430211.xniV3AiSOY@localhost> In-Reply-To: <5430211.xniV3AiSOY@localhost> Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-user@lists.gentoo.org Reply-to: gentoo-user@lists.gentoo.org MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201105252207.47238.alan.mckinnon@gmail.com> X-Archives-Salt: X-Archives-Hash: 84cd7821093b29df73b1aa3f4a265f95 Apparently, though unproven, at 18:53 on Wednesday 25 May 2011, Volker Armin Hemmann did opine thusly: > On Wednesday 25 May 2011 16:20:58 Alex Schuster wrote: > > So, 27 minutes to put 885MB of swap back into RAM, with the double amount > > of that being free RAM. I monitored with iotop, and the transfer rate > > started around 60-100 K/s, later it went higher. But the average > > transfer rate is 550K/s. Shouldn't swap be, like, a little faster? > > no, sounds about right. Swap in linux is brain damaging slow. If you think > about it your gall bladder might explode. That slow. For years now I've considered only two possible uses for linux swap: - a teeny small one just for wiggle room to try and hold that POS called the oom killer at bay - a bigger one the same size as total RAM, as a place to put the suspend image Every other usage makes no sense at all (RAM being so cheap and all). In fact, I've banned swap on all company servers except databases. I'd be interested to hear any current use cases where swap delivers a provable benefit. -- alan dot mckinnon at gmail dot com