Hi all,
Last week I decided to switch from postgresql to mysql to test
differences in performance. I run a 400MB dbmail database on a single
cpu PPro180. Postgres was ok, but sometimes performance was somewhat
sub-par. Messages appeared empty in my message-pane, copy-to-sent on
send failed most of the time, and more stuff like that.
Switching to mysql was totally painless. However performance sucked
major. Switching from myisam to innodb only made things worse. My
machine is resource poor in cpu and memory and the load rose from .5
running on postgresql to a sustained 6.0 :-(
Trying to switch back to postgres was a dead-end: the mysql2pgsql
scripts in de dbmail package turned out to be less than perfect. Or was
it my postgres installation. Importing data into postgres barfed
whenever a messageblk contained a md5 hash complaining about illegal
MULE_INTERNAL characters. Any one any clue ? I think nice, documented,
clean migration procedures for mysql <-> postgresql would by a boon.
Being unable to move back to postgres I had to sweat it out. Not so much
it seemed: adding a sloth of indexes to the main tables solved all
performance issues I had. Using innodb I decided to add foreign key
contraints, and dbmail now feels very snappy indeed. Load now hovers
below 0.1 :-)
So my question to Roel, Eelco et et.: Why are those indexes not part of
the create_table statements ? And why are foreign key contraints not
part of the create_table statements for innodb and postgresql ?
regards,
--
________________________________________________________________
Paul Stevens mailto:[EMAIL PROTECTED]
NET FACILITIES GROUP PGP: finger [EMAIL PROTECTED]
The Netherlands________________________________http://www.nfg.nl
