-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Andreas Jung wrote: > > > --On 12. Juli 2006 15:54:29 +0000 > [EMAIL PROTECTED] wrote: > >> >> Hi :) >> >> I am to use Zope on a SMP machine which has 2 Xeon HT cpus (so 4 logical >> processors). As far as I know Python is not multithreaded, so the full >> potential of the server will not be used... How can I change that? > > There is nothing you can change. One Zope instance or ZEO instance per CPU. > >> >> I was thinking about running a couple of identical instances connected >> with ZEO and then using some load balancing between them. > > THat's the standard way > >> Do you think >> this is a good idea? > > Why shouldn't that be a good idea? > >> How many instances should I use on a machine I have >> described, four?
YMMV. E.g.: - Try loading up four appserver instances, and compare throughput with two instances. - Over time, the SMP kernel should migrate each appserver process to its own CPU, once it notices thatt threads within each process end up contending for a per-process resource (the Python GIL). - Benchmark your stress test (against the load-balanced IP), keeping an eye on memory consumption. I would recommend giving such a box at least 4 Gb of RAM (assuming four appservers running). - Play around with the zope.conf setting for Python's sys.setcheckinterval value (I don't recall the spelling right off). - Tweak the number of appserver threads, as well (e.g., maybe two instead of 4, or maybe 6). You may need to dial up or down the ZODB connection pool size as well (It should be at least one or two connections larger than the number of appserver threads). > Since hyperthreaded CPUs share one real CPU you won't give much performance > over running four processes on two real CPUs...I haven't much > performance improvements in using hyperthreading over using real CPUs. I have heard anecdotal evidence that running 4 appserver instances on a dual-core dual-CPU box worked best in one application under load. I don't recall what number of threads they ended up using per appserver instance, nor what checkinterval setting they settled on. Tres. - -- =================================================================== Tres Seaver +1 202-558-7113 [EMAIL PROTECTED] Palladion Software "Excellence by Design" http://palladion.com -----BEGIN PGP SIGNATURE----- Version: GnuPG v184.108.40.206 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFEtRtk+gerLs4ltQ4RAvzgAJ9sLxMgZB5r9E9fK1Q1sxIEvgstGgCgv49z T/ugMuJrTbbOR3Y+6ggxOts= =5Qs7 -----END PGP SIGNATURE----- _______________________________________________ Zope maillist - Zope@zope.org http://mail.zope.org/mailman/listinfo/zope ** No cross posts or HTML encoding! ** (Related lists - http://mail.zope.org/mailman/listinfo/zope-announce http://mail.zope.org/mailman/listinfo/zope-dev )