We're using ZFS on a V440 for our Cyrus spools that are on a 6920 and all I have to say is KICK A$$!!! ;-) ZFS will use as much memory as you can spare for caching, but it hasn't really caused us any problems. At first it made us nervous because it seemed like all our free memory disappeared (of course a leak in PAM/saslauthd didn't help.) However, it has turned out to be fine. And yes, compression is on. At first I was anxious about that, but it has turned out to be a total non-issue. So far we've been extremely happy with ZFS. In fact a short while ago we had a cooling problem with the particular server room this equipment is in, and to make matters worse the temperature warning sensor failed us. So the heat got high enough that things started shutting down on their own, including our Cyrus server. CRAP! I know for a fact that VxFS would have had to fsck the entire spools before they would come back. That probably would have taken a day. If we had to do a restore from tape, oh my that would have been nasty! However, ZFS came back instantly without the slightest hint of problems. Things have been running swimmingly (knock on wood) since then. On 4/24/07, Vincent Fox <vbfox@xxxxxxxxxxx> wrote:
Has anyone attempted using ZFS compression on mail spools? This is a new Cyrus 2.3.8 mail-store, and we are using dual fiber HBA to SAN switches and Sun 3510FC units on the backend, multipath and active-active on the dual-controllers. RAID-5 LUNs on each array are ZFS mirrored between arrays. Yes, multiple levels of paranoia. We have Sun T2000 which are quad-CPU. So it seems like there is plenty of CPU there for the extra overhead that inline compression is likely to add. Anyhow, I still envision the I/O being the bottleneck though so I am wondering if turning this on will buy me any performance and at what price? This system is not in production yet so I am still throwing things at it to see at what point it breaks. ---- 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
---- 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
