On Wednesday 21 December 2005 20:14, Stephen Frost wrote: > * Madison Kelly (linux@xxxxxxxxxxx) 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.
