Re: random_page_costs - are defaults of 4.0 realistic for SCSI RAID 1 - Mailing list pgsql-performance

From Mark Mielke
Subject Re: random_page_costs - are defaults of 4.0 realistic for SCSI RAID 1
Date
Msg-id 46E5AEA8.4010809@mark.mielke.cc
Whole thread Raw
In response to Re: random_page_costs - are defaults of 4.0 realistic for SCSI RAID 1  ("Luke Lonergan" <llonergan@greenplum.com>)
List pgsql-performance
Luke Lonergan wrote:
> Should be a lot higher, something like 10-15 is approximating accurate.
>
In my own case, I have a much smaller database that I normally work
with, where everything should fit in memory (100 Mbytes?), and reducing
it to 3.0 has resulted in consistently better timings for me. I think
this means that the planner doesn't understand my database size :
effective memory size ratio. :-)

Anyways - my point is that if you change the default to 10 you may hurt
people like me.

Cheers,
mark

--
Mark Mielke <mark@mielke.cc>

pgsql-performance by date:

Previous
From: "Luke Lonergan"
Date:
Subject: Re: random_page_costs - are defaults of 4.0 realistic for SCSI RAID 1
Next
From: Josh Berkus
Date:
Subject: Re: random_page_costs - are defaults of 4.0 realistic for SCSI RAID 1