Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!husc6!rice!sun-spots-request
From: munnari!cs.mu.oz.au!kre@uunet.uu.net (Robert Elz)
Newsgroups: comp.sys.sun
Subject: Re: newfs: decreasing bytes/inode
Keywords: SunOS
Message-ID: <1342@murtoa.cs.mu.oz.au>
Date: 25 Apr 89 20:36:14 GMT
References: <8902240330.AA13943@csvax.caltech.edu> <558@igor.Rational.COM>
Sender: usenet@rice.edu
Organization: Sun-Spots
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Original-Date: 6 Apr 89 19:29:39 GMT
X-Sun-Spots-Digest: Volume 7, Issue 248, message 3 of 13

Don't decrease the block size (on a sun at least), paging requires that
blocks be at least as big as pages (8k on sun 3's and up).

However there's nothing at all that says that any of the other parameters
in disktab *must* relate in any way at all to the drive you're using.

You will (may) get better performance if they do, but that's all the
difference they make.  If the difference is between 5% or 10% performance
on must huge filesystems (/usr/spool/news and user type filesystems rather
than /tmp or /usr) and not having enough inodes to be able to put all the
files that need to be there in the filesystem, I know which I'm going to
choose...

Change the number of sectors, the number of tracks, the number of
cylinders so they end end up multiplying to the right number of blocks, or
close to it, and until you can get enough inodes to survive.

If you can, halve the number of tracks or sectors, and double the number
of cylinders, that will give minimum performance loss, but anything will
do.

kre