Path: utzoo!attcan!uunet!lll-winken!lll-lcc!ames!mailrus!cornell!uw-beaver!rice!sun-spots-request
From: aat@mace.cc.purdue.edu (Jeff Smith)
Newsgroups: comp.sys.sun
Subject: Re: Problems with Fujitsu-M2382K on Xylogic 735 on a 3/280
Message-ID: <8812050105.AA03739@mace.cc.purdue.edu>
Date: 15 Dec 88 09:04:26 GMT
Sender: usenet@rice.edu
Organization: Rice University, Houston, Texas
Lines: 33
Approved: Sun-Spots@rice.edu
Original-Date: Sun, 04 Dec 88 20:05:08 -0500
X-Sun-Spots-Digest: Volume 7, Issue 55, message 12 of 14

> We recently received a Fujitsu-M2382K on Xylogic 735 and I was trying to
> set it flying on a 3/280 when I ran into problems with insufficient inodes
> in the client root partition...

We received a reply from hotline@sun.com that helped us.  We got enough
inodes at the cost of losing about 1% of our data blocks.  I've appended
the suggested workaround.

Jeff Smith

 Work around:
	See the evaluation below. If the user can afford to loose a few
	tracks/sectors, he should remake the filesystem with the third
	scheme discussed above by reducing the number of cylinders/group.
	But now he should make sure that #sector * #tracks should be an
	even number.
	#/etc/mkfs /dev/rxy0e 94086 67 26 8192 1024 8 10 60 2048 t 0
	/dev/rxy0e:     94068 sectors in 54 cylinders of 26 tracks, 67 sectors
        	48.2Mb in 7 cyl groups (8 c/g, 7.14Mb/g, 2048 i/g)
	super-block backups (for fsck -b#) at:
	 32, 14048, 28064, 42080, 56096, 70112, 84128,
	#
	Notice that we have lost 1.8MB of data, #sectors=67, #tracks=26
	and the total number of sectors = 94068.
 Evaluation:
	The number of cylinders per group depend indirectly upon
	fs_cpc (cylinders per cycle in position table) and cpg has
	to be a multiple of cpc. cpc = 16 >> x, where x is the largest
	integer such that "track * sector = N * (2**x)", where N is an
	integer. In this case "track*sector" is an odd number, and hence
	x=0, and hence cpc=16. UFS depends upon the cpc to find out the
	rotational position of the sector. This would be a difficult bug
	to fix. See above workaround. With that one can reduce the number
	of cylinders per group.