Re: Auto-tuning work_mem and maintenance_work_mem

On 10/09/2013 10:07 AM, Bruce Momjian wrote:
> We can have the discussion here or in another thread.  I am thinking the
> right fix is to allocate larger shared_buffers, especially now that we
> don't require a larger System V shared memory segement.  Basically, for
> 128MB of shared buffers, I figured the calculation was fine, and when we
> increase the default shared_buffers, we will then get a better default,
> which is why I am quoting the 2GB shared_buffers defaults in my emails.

Also, it's *worlds* easier to tell users:

"set shared_buffers to 1/4 of your RAM, butnot more than 8GB."

then to tell them:

"set shared_buffers to X, and work_mem to Y, and maintenance_work_mem to
Z ..."

That is, if there's one and only one setting users need to change, they
are more likely to do it.

-- 
Josh Berkus
PostgreSQL Experts Inc.
http://pgexperts.com