For what Cyrus is doing on Solaris with ZFS, the recordsize seems nearly negligible. What with all the caching in the way, and how ZFS orders transactions, it's about the last tuneable I'd worry about. Here's what works well for us, add this to /etc/system: * Turn off ZFS cache flushing set zfs:zfs_nocacheflush = 1 * Increase DNLC (Directory Name Lookup Cache) set ncsize = 500000 Turn off atime of course. Turn on LZJB compression for metapartition but gzip for the mail data filesystem. Our compression ratio on the mail filesystem is showing 1.68x. Our I/O channels average only 4-5% busy with ~6,000 users per backed mailstore. We run nightly snapshots and then backup every other night from the most recent snapshot and that is factored into the iostat number. ---- Cyrus Home Page: http://cyrusimap.web.cmu.edu/ Cyrus Wiki/FAQ: http://cyrusimap.web.cmu.edu/twiki List Archives/Info: http://asg.web.cmu.edu/cyrus/mailing-list.html
