From: | Josh Berkus <josh(at)agliodbs(dot)com> |
---|---|
To: | pgsql-performance(at)postgresql(dot)org |
Cc: | Michael Stone <mstone+postgres(at)mathom(dot)us> |
Subject: | Re: PG8 Tuning |
Date: | 2005-08-17 20:39:47 |
Message-ID: | 200508171339.47399.josh@agliodbs.com |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-performance |
Michael,
> Well, you don't have to spend *quite* that much to get a decent storage
> array. :)
Yes, I'm just pointing out that it's only the extreme cases which are
clear-cut. Middle cases are a lot harder to define. For example, we've
found that on DBT2 running of a 14-drive JBOD, seperating off WAL boosts
performance about 8% to 14%. On DBT3 (DSS) seperate WAL (and seperate
tablespaces) helps considerably during data load,but not otherwise. So it
all depends.
> That's a different creature from
> a data mining app that might really benefit from having additional
> spindles to accelerate read performance from indices much larger than
> RAM.
Yes, although the data mining app benefits from the special xlog disk
during ETL. So it's a tradeoff.
> At any rate, this just underscores the need for testing a
> particular workload on particular hardware
Yes, absolutely.
--
--Josh
Josh Berkus
Aglio Database Solutions
San Francisco
From | Date | Subject | |
---|---|---|---|
Next Message | Merlin Moncure | 2005-08-17 20:40:34 | bitmap scan issues 8.1 devel |
Previous Message | Matthew Nuzum | 2005-08-17 20:33:52 | Re: Need for speed |