From owner-freebsd-questions Sat Apr 27 19: 6:38 2002 Delivered-To: freebsd-questions@freebsd.org Received: from albatross.prod.itd.earthlink.net (albatross.mail.pas.earthlink.net [207.217.120.120]) by hub.freebsd.org (Postfix) with ESMTP id CF11D37B41A for ; Sat, 27 Apr 2002 19:06:32 -0700 (PDT) Received: from sdn-ar-007dcwashp016.dialsprint.net ([63.178.91.24] helo=moo.holy.cow) by albatross.prod.itd.earthlink.net with esmtp (Exim 3.33 #2) id 171e57-00009j-00 for freebsd-questions@freebsd.org; Sat, 27 Apr 2002 19:06:30 -0700 Received: by moo.holy.cow (Postfix, from userid 1001) id 6B7F450B8E; Sat, 27 Apr 2002 22:08:56 -0400 (EDT) Date: Sat, 27 Apr 2002 22:08:56 -0400 From: parv To: f-q Subject: understanding disk slicing & fs layout Message-ID: <20020428020855.GA3416@moo.holy.cow> Reply-To: f-q Mail-Followup-To: f-q Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG i am preparing to repartition & re-slice my drive. currently i have... Filesystem 1K-blocks | Used Avail Capacity| iused ifree | waste/ | | | overhead -----------------------|--------------------------|-----------------|---------- /dev/ad0s2a 496111 | 100109 356314 22% | 2060 122866 | 38.8 MB /dev/ad0s2e 2083854 | 1654378 262768 86% | 72460 451314 | 162.8 MB /dev/ad0s3f 2860982 | 1113524 1518580 42% | 124737 591613 | 223.5 MB /dev/ad0s3e 714447 | 1 657291 0% | 1 179581 | 55.8 MB /dev/ad0s2f 218463 | 193896 7090 96% | 1617 53037 | 17.1 MB -------------------------------------------------------------------------------- total: 6373857 3061908 2802043 -- ------ ------ ----- total in MB: 6224.5 2990.1 2736.4 -- ------ ------ 498 calculated overhead factor, o = 12.5 usable = total - (total/o) total = usable * o/(o - 1) ; 12.5/(12.5 - 1) = 1.08696 ...as you can see the most obvious thing -- besides allocating around 130 MB to / & mounting /tmp as mfs -- to keep in mind for me is to adjust the inode numbers. even when every slice is full, there will still be plenty of inodes left unused. it has been long time since i sliced disk, so during partitioning & slicing disk, is the user asked about adjusting the inodes? another question, how is the factor of 12.5 came about to be (other than being a calculated quantity)? here is what newfs shows for /dev/ad0s2a... Warning: Block size and bytes per inode restrict cylinders per group to 90. /dev/ad0s2a: 1024000 sectors in 250 cylinders of 1 tracks, 4096 sectors 500.0MB in 3 cyl groups (90 c/g, 180.00MB/g, 21120 i/g) super-block backups (for fsck -b #) at: 32, 368672, 737312 ...and, for /dev/ad0s2f ... Warning: Block size restricts cylinders per group to 96. Warning: 3808 sector(s) in last cylinder unallocated /dev/ad0s2f: 450848 sectors in 111 cylinders of 1 tracks, 4096 sectors 220.1MB in 2 cyl groups (96 c/g, 192.00MB/g, 14080 i/g) super-block backups (for fsck -b #) at: 32, 393248 (so far i had read newfs manpage, on to reading disklabel's again.) thanks much. - parv ps: i will appreciate if just mail to -questions & not cc me. but if you can't help yourself, i understand. (: -- To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message