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 1O54I1-0006KF-FJ for garchives@archives.gentoo.org; Thu, 22 Apr 2010 21:50:30 +0000 Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id 30509E07F4; Thu, 22 Apr 2010 21:49:51 +0000 (UTC) Received: from mail-wy0-f181.google.com (mail-wy0-f181.google.com [74.125.82.181]) by pigeon.gentoo.org (Postfix) with ESMTP id E6195E07F4 for ; Thu, 22 Apr 2010 21:49:50 +0000 (UTC) Received: by wyf23 with SMTP id 23so1053070wyf.40 for ; Thu, 22 Apr 2010 14:49:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:from:to:subject:date :user-agent:cc:references:in-reply-to:mime-version:content-type :content-transfer-encoding:message-id; bh=ILHLRltOc2dAtf+/nIw85nihWg4KtbCjPOFCrWlm0Us=; b=EGcYX7lpGv2iWt4Xpgl/zhQN7eV3+iK3J1wGauuG/syT90glwSELjZ0O7do+YCZDEB t/Xc8DTG67xrC0H7U5sMbmKbnU4A3xk4v+i+gh7irmz0G4VydWazhyp6n9jxX4aPWHYp 8SwzEL1tZYa2/YjbUJA4SLPJOIpANFZWw/noA= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=from:to:subject:date:user-agent:cc:references:in-reply-to :mime-version:content-type:content-transfer-encoding:message-id; b=N1D1wUU8DUcwWacyA7U64Mm8qnWm40GG6wUbWTN7o2lq3UI1zdAwmT0evsqJcLXcao c6yVB0sZsUgIBcaECRUeJ3dbgNlYYqEukjpczcteisz++ZdP7CisyX0M2khId1s9Z9d5 UkwLzLJQsW3+VsVvJfDd2P/4AlCtq1gDIoSbE= Received: by 10.216.91.76 with SMTP id g54mr960498wef.2.1271972990247; Thu, 22 Apr 2010 14:49:50 -0700 (PDT) Received: from nazgul.localnet (196-210-153-185-rrdg-esr-2.dynamic.isadsl.co.za [196.210.153.185]) by mx.google.com with ESMTPS id t27sm2863055wbc.5.2010.04.22.14.49.47 (version=TLSv1/SSLv3 cipher=RC4-MD5); Thu, 22 Apr 2010 14:49:48 -0700 (PDT) From: Alan McKinnon To: gentoo-user@lists.gentoo.org Subject: Re: [gentoo-user] Re: gentoo-box stopping services Date: Thu, 22 Apr 2010 23:46:30 +0200 User-Agent: KMail/1.13.2 (Linux/2.6.33-zen1; KDE/4.4.2; x86_64; ; ) Cc: walt References: <4BCD97B0.3050305@xunil.at> <201004221852.05699.alan.mckinnon@gmail.com> In-Reply-To: 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: <201004222346.31271.alan.mckinnon@gmail.com> X-Archives-Salt: 07cc8566-548e-4b66-b0fc-dbab90bd2e38 X-Archives-Hash: 199cb69828f32ac3b1754ecf8ca08577 On Thursday 22 April 2010 23:16:56 walt wrote: > On 04/22/2010 09:52 AM, Alan McKinnon wrote: > > On my web and mail servers I have no swap at all, they do have lots and > > lots of RAM; my Sybase database servers have enormous amounts of swap... > > Hm. Does that mean your database servers are allowed to be slower than the > web and mail servers? No, it means that the database software intelligently handles swap. An enterprise grade db like this one will load many megabytes of data in huge chunks on and off disk in one action. If you are dealing with tables containing many millions of rows, you really do want this behaviour. Without swap, the db will still load and unload many megs of data at a time on and off disk, so there is no appreciable downgrade of performance, but I do have the benefit of keeping data in virtual memory for longer using swap. The database code pages are never swapped by design - doing that is just plan stupid. The web and mail servers on the other hand deal with millions of small files, on the order of 10k each. Allowing that to swap is catastrophic. -- alan dot mckinnon at gmail dot com