[OpenAFS-devel] AFS and ufs/sds logging on solaris

[Nickolai Zeldovich]

> 1.) has AFS been tested on UFS filesystems with
>     logging turned on ? (since Solaris 7)

For cache partitions, UFS logging leads to deadlock if there
is anything else stored on the same partition as the cache.
As far as I can tell, this happens when you copy a file from
AFS onto the cache partition.  The cache manager tries to
write something to the cache partition, and this operation
gets placed in transaction A.  If the cache partition is too
full, the truncate daemon is woken up and tries to truncate
some files, but this operation gets placed into transaction
B.  Now, transaction A can't close until the cache manager
finishes the write, but it's waiting for the truncate daemon
which can't finish either (B can't happen before A).

(If anyone is interested, I could probably find my corefiles
again and get more accurate data on this problem.)

-- kolya