Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!zaphod.mps.ohio-state.edu!rpi!batcomputer!hurf From: hurf@batcomputer.tn.cornell.edu (Hurf Sheldon) Newsgroups: comp.sys.hp Subject: Re: minfree, inodes Message-ID: <1991Feb12.151929.19649@batcomputer.tn.cornell.edu> Date: 12 Feb 91 15:19:29 GMT References: <1991Feb08.161751.13172@eye.com> <17780008@hpfcmgw.HP.COM> Organization: Cornell Theory Center Lines: 53 In article <17780008@hpfcmgw.HP.COM> rocky@hpfcmgw.HP.COM (Rocky Craig) writes: >> I've been setting up filesystem with "newfs -i 8192 -m 5"....Am I crazy? > >Well, check rec.shrink for a second opinion:-) You have to be crazy to worry about this stuff or it would make you nuts. >My group stages tradeshows >for HP, so we create lots of new filesystems on a regular basis. >We have "evolved" into using the values you quoted for a variety of >technical and empirical reasons. . . . All said before is correct except when in a heavily NFS dependent environment. It appears that when the NFS server goes below 20% free space and there are heirarchical read/writes (someone compiling in a server directory on a client) performance drops like a stone. Read only server situations don't exhibit this behavior as badly but a client generated find on a 90% full NFS disk will go much slower than on an 80% full disk. (I don't know why - perhaps fragmentation causing more disk accesses being queued ) The large number of default inodes are long term insurance as well as historically based from the days when a 50mb disc seemed like infinite space- (remember?) as the disc became full it fragmented a lot and every frag needed an inode and besides, who could conceive of having files that were bigger than 100k? Many database applications are inode pigs as well, having beaucoup 3k entries. - Anyway a heavily written to disc seems to need >5% free space to keep performance up but when you get up to 600+mb discs 60mb seems a bit excessive. From a sytem management point of view, because you can change minfree at any time, using 10% initially leaves you with some emergency reserve when it becomes critical. (always at 5pm friday) Inodes are an irreversible (more or less) judgement call - something I have ignored 'til now but looking at a 580mb partition 70% full with 603 inodes used and 157094 (150k!) free it won't get ignored again. Thanks Paul! Hurf -- Hurf Sheldon Network: hurf@theory.tn.cornell.edu Program of Computer Graphics Phone: 607 255 6713 580 Eng. Theory Center, Cornell University, Ithaca, N.Y. 14853