On Wed, Jan 31, 2007 at 03:26:09PM +0530, Ramprasad wrote: > I was reading performance tuning information at > > http://cyrusimap.web.cmu.edu/imapd/install-perf.html > I too have a large cyrus setup with minimum 600+ connections at a time > We are upgrading to a 8GB Ram Dual Xeon box , I want to make sure we use > the hardware optimally > > The document talks of increasing cache size in cyrus source which file > do I change ? > > I made this change to the source ( patch file ). Will it work > > > > Index: lib/imapoptions > =================================================================== > --- lib/imapoptions (.../cyrus-2.3.7-DEFAULT) (revision 134) > +++ lib/imapoptions (.../cyrus) (revision 134) > @@ -155,7 +155,7 @@ > creating the mailbox INBOX. The user's quota is set to the value > if it is positive, otherwise the user has unlimited quota. */ > > -{ "berkeley_cachesize", 512, INT } > +{ "berkeley_cachesize", 4096, INT } > /* Size (in kilobytes) of the shared memory buffer pool (cache) used > by the berkeley environment. The minimum allowed value is 20. The > maximum allowed value is 4194303 (4GB). */ No need to patch the code for that - it's an option! Just put: berkeley_cachesize: 4096 in your /etc/imapd.conf We use skiplist for our mailboxes.db and we haven't seen any issues that were caused by leaving that at its default value. That said: % cat $confdir/db/DB_CONFIG set_cachesize 0 2097152 1 set_lg_regionmax 2097152 set_lg_bsize 2097152 set_lg_max 16777216 set_tx_max 200 set_tas_spins 1 % (and no, I didn't set that up, so I'm not sure why all those values. It works for us though) Sounds like your hardware should cope OK with 600 connections: [root@imap2 root]$ netstat -n -a | grep :2143 | wc -l 2232 And that's at one of our least busy times. I expect it goes up to 2 or 3 times that during the U.S. day. NOTE: we're using reiserfs for our drives, and that machine has 42 partitions split over 8 different raidsets via two separate SCSI controllers, and a split meta configuration that puts the meta data on RAID1 for speed. Still, it's possible to get an order of magnitude more connections out of that sort of spec. That's 8Gb of memory in that machine, and dual hyperthreading Xeons: model name : Intel(R) Xeon(TM) CPU 2.40GHz stepping : 7 cpu MHz : 2394.878 (there's some headroom left with the memory still too...) -/+ buffers/cache: 6118564 2193000 Bron. ---- 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
