On Sat, 6 Oct 2007, Rob Mueller wrote: > Are you comparing an "old" reiserfs partition with a "new" ext3 one where > you've just copied the email over to? If so, that's not a fair comparison. No, a newly created partitions in both cases. Fragmented partitions are slower still of course. > Give it a month or two of active use though (delivering new emails, > deleting old ones, etc), and everything starts getting fragmented again. > Then ext3 really started going to crap on us. Machines that had been > absolutely fine under reiserfs, the load just blew out to unuseable > under ext3. We've only been using ext3 for about 3 months now, so I may still have this to look forward to :). > Talking with Chris Mason about this, data=journal is faster in certain > scenarios with lots of small files + fsyncs from different processes, > exactly the type of workload cyrus generates! I can't see much difference on our Cyrus systems, but battery backed write cache on our RAID controllers probably masks a lot of the change. I agree that it theory it should make a very substantial difference. > As it turns out, the memory leaks weren't critical, because the the > pages do seem to be reclaimed when needed, though it was annoying not > knowing exactly how much memory was really free/used. Okay, I think that we had a different kernel memory bug. We were running out of memory after 24 hours, and a 20 line test program could exhaust memory in seconds. This bug was in SLES four years back, and it was still there the last time that I looked (some months back now). -- David Carter Email: David.Carter@xxxxxxxxxxxxx University Computing Service, Phone: (01223) 334502 New Museums Site, Pembroke Street, Fax: (01223) 334679 Cambridge UK. CB2 3QH. ---- 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
