4.3 BSD VAX 11/750 does not seem to sync its disks.

[Bob Brankley]

I have been having a pretty wild problem on my VAX 11/750 running 4.3
BSD and I would like to see if anybody else is having the same problem.
It seems that 4.3 BSD is not periodically syncing in core inodes out to
disk, resulting in crashes.  My VAX has an RA60 partitioned a-b-f and an
RA81 partitioned a-b-g-h.  The RA81 is the disk giving me the trouble.

I originally found the problem when my nightly "fsck" of the file system
detected multiple UNREFerenced files in the partition containing my user
files(/dev/ra0g).  Attempts to fix the mounted file system ALWAYS resulted in
crashing the system and, hence, I learned not to do that any more.  At
the same time the system would also sporatically crash due to panic "pagein
mfind" during times of heavy usage.

The last time I racked up about 20 UNREFerenced files in my user file
system I decided to check the bad inodes against those already resident
in core.  ALL of the UNREFerenced files were pure text images whose
inodes were kept in core.  To make matters worse, the inodes in core
reported 0 link counts.  Somehow this does not seem right to me.

I have tried fixing the problem by calling sync several dozen times, but
this does not always seem to work.  In fact, the only sure-fire way to
fix the problem seems to be unmounting and remounting the file system. 
Besides, I thought /etc/update was supposed to flush in core inodes, or
does it just flush the superblock?  What does "panic:pagein mfind"
supposed to indicate anyway?  The source code would seem to suggest that
the kernel could not find a page of text that it was supposed to find. 
Is that correct?

Any insight on the matter would be of great help.  Although it is not a
MAJOR inconvenience, I would like to run my system without having to
remount /dev/ra0g every few days.  Thanks for your help in advance.


Bob Brankley
University of South Florida, Engineering Computing Services
CSNET:  usfvax1!brankley at usf.edu
UUCP:   {ihnp4!codas, gatech}!usfvax2!usfvax1!brankley