From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cuda.sgi.com (cuda1.sgi.com [192.48.157.11]) by oss.sgi.com (8.14.3/8.14.3/SuSE Linux 0.8) with ESMTP id q5CItZiZ024285 for ; Tue, 12 Jun 2012 13:55:35 -0500 Received: from mail.sandeen.net (sandeen.net [63.231.237.45]) by cuda.sgi.com with ESMTP id EjOlQxDgTTd5nb5U for ; Tue, 12 Jun 2012 11:55:33 -0700 (PDT) Message-ID: <4FD790A4.8010907@sandeen.net> Date: Tue, 12 Jun 2012 13:55:32 -0500 From: Eric Sandeen MIME-Version: 1.0 Subject: Re: block sizes > 4K ?? possible w/large page support? References: <4FD5643F.5070801@tlinx.org> <4FD6AA2A.3020502@sandeen.net> <4FD77E45.8010402@tlinx.org> In-Reply-To: <4FD77E45.8010402@tlinx.org> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: xfs-bounces@oss.sgi.com Errors-To: xfs-bounces@oss.sgi.com To: "Linda A. Walsh" Cc: xfs-oss On 6/12/12 12:37 PM, Linda A. Walsh wrote: > > > Eric Sandeen wrote: >> On 6/10/12 10:21 PM, Linda A. Walsh wrote: >>> Is this something being thought about?? >>> >>> More than one of my hard disks: >>> >>> /boot: 130 files in 103112 4K blocks: 793.6 blks/file >>> /tmp: 1401 files in 746715 4K blocks: 533.4 blks/file >>> /var/cache: 1438 files in 87858 4K blocks: 61.5 blks/file >>> /backups: 713 files in 2523985177 4K blocks: 3539951.6 blks/file >>> /var: 9038 files in 746715 4K blocks: 83.1 blks/file >>> /var/cache/squid: 570 files in 90031 4K blocks: 158.4 blks/file >>> /Media: 51893 files in 1691400956 4K blocks: 32594.5 blks/file >>> /: 37312 files in 506778 4K blocks: 14.0 blks/file >>> /usr/share: 320805 files in 195425485 4K blocks: 609.6 blks/file >>> /backups/Media: 50544 files in 1642550112 4K blocks: 32497.9 blks/file >>> /usr: 116650 files in 1389380 4K blocks: 12.4 blks/file >>> /Share: 1617995 files in 305269701 4K blocks: 189.1 blks/file >>> /home: 5822174 files in 195412389 4K blocks: 34.0 blks/file >>> >>> All but 2 could benefit from a 16K block size, and 3 of them could benefit >>> from a 128K block size. Wouldn't that benefit in in freeing up some space >>> both on disk and in memory? Just a thought. >> >> Since on average each file in an evenly-distributed filesystem wastes half >> a block, in theory each fs would waste 4x more space w/ 16k blocks than >> 4k blocks, right? > --- > Well the real candidates for a larger block size would be backups, > and maybe Media... the rest wouldn't benefit. > > So, it sounds like I might just as well benefit by going to a 1K > block size, if there's no cost in smaller block sizes? Or would that be > entirely dependent on the files/dir? Well, there are some metadata overhead costs there, so it's a tradeoff. Like we always say, use the defaults unless you can definitively show that other options work better for your needs after testing. :) -Eric _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs