On Wed, Mar 25, 2015 at 09:03:54AM -0400, Phil Stracchino wrote: > On 03/25/15 08:48, k...@rice.edu wrote: > > On Wed, Mar 25, 2015 at 06:39:43AM -0300, j...@7lan.net wrote: > >> I'm planning to put it in a sql backend. What database does dspam works > >> better? I saw some postgresql schema optimization, but maybe mysql is > >> less resource eater? What are your experiences? > > > We currently use MySQL with a MyISAM backends with an old release of DSPAM, > > version 3.6.x. We are working on an upgrade to the latest release of DSPAM > > and change to a PostgreSQL backend to allow us to partition that backend > > tables which will allow us to perform maintenance more easily without > > impacting concurrent usage: use CLUSTER to keep user tokens adjacent, use > > a <100% fill-factor to allow for HOT updates, remove old mail signatures > > with TRUNCATE and not DELETE. Note, for as many users as you have, you > > may not want to keep the signatures at all and simply retrain the message > > if you have it available. The resource usage between MySQL and PostgreSQL > > is similar, as far as I know once you move to InnoDB/XtraDB. > > It's probably worth pointing out that MyISAM is a legacy storage engine > which, realistically, should not be used in production any more except > when strictly unavoidable. "Conventional wisdom" has it that MyISAM is > faster than InnoDB for mostly-read loads; benchmarking performed at my > employer indicates that this is not actually the case, and that InnoDB > substantially outperforms MyISAM even for a 100% read workload, the best > possible performance case for MyISAM. MyISAM is not robust, not ACID > compliant, and does not perform well; the only reason to use it is if > minimum resource utilization is an overriding priority, or if you are > using one of the few remaining MyISAM features not yet supported (or not > supported well) by InnoDB. (Currently this pretty much means SPATIAL > indexes, which aren't supported yet in InnoDB, and FULLTEXT indexes, > which don't perform well yet.) >
Exactly why we are moving to PostgreSQL in the update. When we first set up the old version, InnoDB performance was very poor and PostgreSQL had other problems. Since then, both products have improved greatly! It should also be noted, that MyISAM also performs poorly for mixed read-write activities due to the locking needed to coordinate access. If fact, we had to use multiple DBs to keep locking to a manageable level in each DB. SPATIAL and FULLTEXT indexes are not really applicable to DSPAM. Regards, Ken ------------------------------------------------------------------------------ Dive into the World of Parallel Programming The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net/ _______________________________________________ Dspam-user mailing list Dspam-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/dspam-user
