Re: Initial prefetch performance testing - Mailing list pgsql-hackers

From Bruce Momjian
Subject Re: Initial prefetch performance testing
Date
Msg-id 200809241428.m8OESsi22353@momjian.us
Whole thread Raw
In response to Re: Initial prefetch performance testing  (Ron Mayer <rm_pg@cheapcomplexdevices.com>)
Responses Re: Initial prefetch performance testing  (Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>)
List pgsql-hackers
Ron Mayer wrote:
> Even more often on systems I see these days, "spindles"
> is an implementation detail that the DBA has no way to know
> what the correct value is.
> 
> For example, on our sites hosted with Amazon's compute cloud (a great
> place to host web sites), I know nothing about spindles, but know
> about Amazon Elastic Block Store[2]'s and Instance Store's[1].   I
> have some specs and are able to run benchmarks on them; but couldn't
> guess how many spindles my X% of the N-disk device that corresponds
> to.  For another example, some of our salesguys with SSD drives
> have 0 spindles on their demo machines.
> 
> I'd rather a parameter that expressed things more in terms of
> measurable quantities -- perhaps seeks/second?  perhaps
> random-access/sequential-access times?

I assume SAN users might not know the number of spindles either.

--  Bruce Momjian  <bruce@momjian.us>        http://momjian.us EnterpriseDB
http://enterprisedb.com
 + If your life is a hard drive, Christ can be your backup. +


pgsql-hackers by date:

Previous
From: KaiGai Kohei
Date:
Subject: Re: Updates of SE-PostgreSQL 8.4devel patches
Next
From: Bruce Momjian
Date:
Subject: Re: Initial prefetch performance testing