Re: Beowulf Cluster & Postgresql?

On Wed, 2004-07-21 at 14:45, joe wrote:
> Hi all,
>     I was wondering if part or all of Postgres would be able to take
> advantage of a beowulf cluster to increase performance?  If not then why
> not, and if so then how would/could it benefit from being on a cluster?
>
>     Thanks for the enlightenment in advance.

That type of clustering helps with large parallel processes that are
loosely interrelated or none at all.

In PostgreSQL, as in most databases, all actions that change the data in
the database tend to be highly interrelated, so it becomes very
expensive to pass all that locking information back and forth.  The very
thing a cluster would be good at, lots of reads, very few writies, is
the antithesis of what postgresql is built to be good at, lots of writes
as well as lots of reads.

Basically, clustering tends to make the database faster at reads and
slower at writes.  While there are clustering solutions out there,
Beowulf clustering is oriented towards highly parallel CPU intensive
workloads, while PostgreSQL tends to be I/O intensive, and since all the
data needs to be stored in one "master" place, adding nodes doesn't
usually help with making writes faster.