We have this situation with one of our NW6SP5 servers: the reported
percentage used on its NSS volumes sometimes increases substantially
during the day, even though virtually no new files are being written to
the volumes. When the server is restarted the correct (lower) percentage
used numbers reappear.

I understand that there was an issue along these lines that was resolved
with SP5, but we have SP5 installed on the problem server and it still
does this.

Any thoughts?