Re: MySQL is faster than PgSQL but a large margin in my program... any ideas why?

On Wednesday 21 December 2005 20:14, Stephen Frost wrote:
> * Madison Kelly (linux@alteeve.com) wrote:
> >   If the performace difference comes from the 'COPY...' command being
> > slower because of the automatic quoting can I somehow tell PostgreSQL
> > that the data is pre-quoted? Could the performance difference be
> > something else?
>
> I doubt the issue is with the COPY command being slower than INSERTs
> (I'd expect the opposite generally, actually...).  What's the table type
> of the MySQL tables?  Is it MyISAM or InnoDB (I think those are the main
> alternatives)?  IIRC, MyISAM doesn't do ACID and isn't transaction safe,
> and has problems with data reliability (aiui, equivilant to doing 'fsync
> = false' for Postgres).  InnoDB, again iirc, is transaction safe and
> whatnot, and more akin to the default PostgreSQL setup.
>
> I expect some others will comment along these lines too, if my response
> isn't entirely clear. :)

Is fsync() on in your postgres config?  If so, that's why you're slower.  The 
default is to have it on for stability (writes are forced to disk).  It is 
quite a bit slower than just allowing the write caches to do their job, but 
more stable.  MySQL does not force writes to disk.