For what it's worth, we've found ext3 to be far too slow for our needs. The best setup we've found is reiserfs, mounted with "noatime" and "notail" options -
Joe Brandon Hilkert wrote: > ----- Original Message ----- From: "Ralf Hildebrandt" > <ralf.hildebra...@charite.de> > To: <postfix-users@postfix.org> > Sent: Friday, March 20, 2009 6:52 AM > Subject: Re: Performance tuning > > >> * Brandon Hilkert <bhilk...@vt.edu>: >> >>> We send out a pretty volume of emails right now using a combination of >>> SQL and IIS SMTP. We get rates now of about 5,000/min. We're looking to >>> not only improve the rates, but incorporate DKIM/Domainkey signing into >>> the process. The choice has been made to go with postfix along with a >>> queue directory on an XFS file system. >> >> You can check if the disk I/O is the bottleneck by simply putting the >> queue fs in a RAM disk! >> > > Sorry if this is a stupid question, but how do I go about this. I tried: > > mkdir /ram > mount -t ramfs none /ram > > and when I send a mail, postfix says there's not enough space in the > queue. Should I be doing it a different way? > > I also put the queue directory back on an ext3 partition and the rates > went up by about a factor of two. > > Also, by default the syslog messages were already set with " > -/var/log/mail.log". I disabled mail logging all together and found no > change in rates. > > My disk is writing about 3 MB/s which should be well within it's > range. I would hope even larger, but I would like to work out the > ramfs and test for sure. > > >>> I'm using postfix as a relay, and having it sign the outgoing emails >>> with DKIM. That process was about twice as slow as without it. Without >>> DKIM, I'm getting a rate of 700/min. >> >> Signing takes time! htop will tell you IO rates and CPU usage... >> >> -- >> Ralf Hildebrandt >> Postfix - Einrichtung, Betrieb und Wartung Tel. +49 (0)30-450 >> 570-155 >> http://www.computerbeschimpfung.de >> "Windows 95 /n./ 32 bit extensions and a graphical shell for a 16 bit >> patch to an 8 bit operating system originally coded for a 4 bit >> microprocessor, written by a 2 bit company that can't stand 1 bit of >> competition." >
