[ZODB-Dev] Re: [Enhancement Proposal] Memory size limited Cache
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Jim Fulton wrote: Dieter Maurer wrote: Jim Fulton wrote at 2006-10-6 12:21 -0400: ... We would have a use case for this, too. We've started moving toward just using a single application thread per process (with many processes). There isn't really much advantage in running multiple threads if you have multiple processes. Apart from sharing resources, such as the cache That isn't a benefit of multiple threads. It is a way to mitigate the cost of multiple threads. In the presence of the GIL there is no throughput benefit in running multiple threads. The only benefit of multiple threads is that it is somewhat less likely that expensive requests will block inexpensive ones. Assuming that you aren't disk or RAM constrained, I'll agree that running multiple processes is more likely to win, especially on multi-CPU machines. However, most sites which have such needs might do better to have a single, *large* cache, than many smaller ones; swapping will kill any benefit obtained from better parallelism. Tres. - -- === Tres Seaver +1 202-558-7113 [EMAIL PROTECTED] Palladion Software Excellence by Designhttp://palladion.com -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.2.2 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFFJq6R+gerLs4ltQ4RAhqsAJ97DfKF64DExcGCadOCBZElvf+KlQCfXdVx LBY1UlywAjTiNqwZJ3JsXcE= =eIaF -END PGP SIGNATURE- ___ For more information about ZODB, see the ZODB Wiki: http://www.zope.org/Wikis/ZODB/ ZODB-Dev mailing list - ZODB-Dev@zope.org http://mail.zope.org/mailman/listinfo/zodb-dev
[ZODB-Dev] Re: [Enhancement Proposal] Memory size limited Cache
Tres Seaver wrote: -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Jim Fulton wrote: Dieter Maurer wrote: Jim Fulton wrote at 2006-10-6 12:21 -0400: ... We would have a use case for this, too. We've started moving toward just using a single application thread per process (with many processes). There isn't really much advantage in running multiple threads if you have multiple processes. Apart from sharing resources, such as the cache That isn't a benefit of multiple threads. It is a way to mitigate the cost of multiple threads. In the presence of the GIL there is no throughput benefit in running multiple threads. The only benefit of multiple threads is that it is somewhat less likely that expensive requests will block inexpensive ones. Assuming that you aren't disk or RAM constrained, I'll agree that running multiple processes is more likely to win, especially on multi-CPU machines. However, most sites which have such needs might do better to have a single, *large* cache, than many smaller ones; swapping will kill any benefit obtained from better parallelism. Sure. I would definitely not run more processes than processors (assuming that the processes are identical). And I wouldn't use more than one thread unless responsiveness was an issue, as it sometimes is. Jim -- Jim Fulton mailto:[EMAIL PROTECTED] Python Powered! CTO (540) 361-1714http://www.python.org Zope Corporation http://www.zope.com http://www.zope.org ___ For more information about ZODB, see the ZODB Wiki: http://www.zope.org/Wikis/ZODB/ ZODB-Dev mailing list - ZODB-Dev@zope.org http://mail.zope.org/mailman/listinfo/zodb-dev
