Out of inodes. SunOS4.0, gripe.

[Felix Lee]

Ran out of inodes yesterday on our /usr/spool partition.  A painful
experience.  C News is mostly graceful in the presence of full disks,
but does nothing to protect you from running out of inodes.

We ran out of inodes because the best we can get from SunOS4.0.3 on
these huge NEC disks we have is one inode per 6.25kbytes.  If you
average less than 6.25kbytes per file you run out of inodes before you
run out of disk space.  Pretty silly.

The reason it's 6.25kbytes per inode is the (historical) maximum
inodes per cylinder group is 2048, and cylinder groups are 14mbytes.
Cylinder groups are that large because, (a) there are 27 * 67 sectors
per cylinder, (b) there are 16 sectors per block, therefore (c) you
need 16 cylinders to fit an even number of blocks without wastage.

Unworkarounds are (a) decrease block size (SunOS wants at least 8K),
(b) increase MAXIPG from 2048 (no kernel source), (c) allow wastage in
cylinder groups (ditto).

Workarounds?  Right now we're expiring news at a (relatively) furious
rate.  The filesystem is at 65% capacity and using 85% of the inodes.

Sigh.
--
Felix Lee	flee at shire.cs.psu.edu	*!psuvax1!flee