AFS can't really cause "san issues" in that it's just another application using your filesystem. In some cases, it can be quite a heavy user of such, but since its only interacting through the fs, its not going to know anything about your underlying storage fabric, or have any way of targeting it for any more badness than any other filesystem user.
One of the big differences that would effect the filesystem IO load that occurred between 1.4.1 & 1.4.6 was the removal functions that made copious fsync operations. These operations were called in fileserver/volserver functions that modified various in-volume structures, specifically file creations and deletions, and would lead to rather underwhelming performance when doing vos restores, deleting, or copying large file trees. In many configurations, this causes the OS to pass on a call to the underlying storage to verify that all changes written have been written to *disk*, causing the storage controller to flush its write cache. Since this defeats many of the benefits (wrt I/O scheduling) on your storage hardware of having a cache, this could lead to overloaded storage.
Some storage devices have the option to ignore these calls from devices, assuming your write cache is reliable.
Under UFS, I would suggest that you'd be running in 'logging' mode when using the namei fileserver on Solaris, as yes, fsck is rather horrible to run. Performance on reasonably recent versions of ZFS were quite acceptable as well.
Anyhow, hope this is of some help. -rob _______________________________________________ OpenAFS-info mailing list [email protected] https://lists.openafs.org/mailman/listinfo/openafs-info
