Alain Spineux a écrit : > On Mon, Apr 28, 2008 at 11:31 PM, Eric Déchaux <Eric.Dechaux@xxxxxxx> wrote: > >> Dear all, >> >> >> I have juste setup a Cyrus infrastructure based on VMware Virtual >> Infrastructure 3.0.1 and I have a huge performance problem. >> >> The new infrastructure was sized for 120 000 mailboxes with 42 000 >> maximum concurrent IMAPS sessions (neither POP3 nor IMAP available). The >> important point is the concurrent sessions count rise from 6 000 to 42 >> 000 in less than an hour, at the beginning of the day when everybody >> starts to work. >> >> >> The hardware is made of two Sun Microsystems X4600 chassis with 8 dual >> core AMD Opteron 885, 64 Gb RAM, 2 dual port 4G QLogic HBA and 4 Intel >> e1000 NIC (2 being used for ESX System Console and VMotion). LAN backend >> is 100% Giga Ethernet, SAN backend is 100% 4 Gb FC. >> >> >> The Virtual machines are running Debian Etch 4.0r3 AMD64 and Cyrus 2.2 >> and are configured as follow : >> >> On each physical server : >> >> - 4 frontends : 2 vCPU, 8 Gb RAM, 8 Gb SWAP / Total 8 vCPU, 32 Gb RAM >> - 3 backends : 4 vCPU, 8 Gb RAM, 8 Gb SWAP, ~500 Gb reizerfs storage >> through a 550 Gb VMFS LUN / Total 12 vCPU, 24 Gb RAM, 1.5 Tb storage >> - 1 webmail : 2 vCPU, 2 Gb RAM, 2 Gb SWAP >> - 1 smtp : 2 vCPU, 2 Gb RAM, 2 Gb SWAP >> - 1 mupdate : 2 vCPU, 2 Gb RAM, 2 Gb SWAP >> >> Total : 26 vCPU, 62 Gb RAM. >> >> >> This infrastructure is the consolidation of an existing one that runs >> Debian Sarge 3.0 i386 with 8 frontends and 5 backends. Each server is a >> dual Intel Xeon 3.0 Ghz with 4 Gb RAM and 4Gb SWAP. >> >> >> The older infrastructure can stand the 42 000 concurrent sessions, the >> new one can't : I was expecting each frontend to be able to handle 5 500 >> concurrent sessions but they are not. Around 3 000 / 3 500 concurrent >> sessions the frontends begin to SWAP and are not more able keep up the load. >> > > At least you know your problem :-) SWAP should be easier to solve than > IO or CPU problem. > I suppose your old frontends where never (or rarely) swapping ! You have replaced 2 old frontents with 4Gb by 1 bigger with 8Gb ! Something in the new configuration > make the new frontent swap! > On current production platform the frontends use swap massively but the impact is far less than on the new platform. > Do you use 64bits software, 64bits OS ? > We are indeed using 64bits OS and 64bits software. This is the main difference between the old platform which runs a 32 bits software on a 32 bits OS. > Are you sure all the 8Gb are available to your applications or are in use ? > I think they are but maybe you can give me a clue to check this and be sure ? > Can you give a list of all configuration and software changes between > old and new configuration ? > Except moving from i386 to AMD64, the software changes are the one included in Debian Etch. This include moving from a 2.6.9 kernel (I think, not sure though) to a 2.9.18. Cyrus version went from 2.1 to 2.2. > Regards Many thanks. -- Eric ---- 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
