Re: improving write performance for logging application

On Tue, Jan 03, 2006 at 04:44:28PM -0700, Steve Eckmann wrote:
> Are there general guidelines for tuning the PostgreSQL server for this kind
> of application? The suggestions I've found include disabling fsync (done),

Are you sure you really want this? The results could be catastrophic in case
of a crash.

> On the client side I've found only two suggestions: disable autocommit and
> use COPY instead of INSERT. I think I've effectively disabled autocommit by
> batching up to several hundred INSERT commands in each PQexec() call, and
> it isn’t clear that COPY is worth the effort in our application.

I'm a bit confused here: How can you batch multiple INSERTs into large
statements for MySQL, but not batch multiple INSERTs into COPY statements for
PostgreSQL?

Anyhow, putting it all inside one transaction (or a few) is likely to help
quite a lot, but of course less when you have fsync=false. Bunding multiple
statements in each PQexec() call won't really give you that; you'll have to
tell the database so explicitly.

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