Database is vacuumed nightly. Matter of fact, it was vacuumed just
prior to the start of the update!
-Jason.
-----Original Message-----
From: K.T. [mailto:kanet@calmarconsulting.com]
Sent: Tuesday, March 30, 1999 2:35 PM
To: Statistical Solutions; pgsql-general@postgreSQL.org
Subject: Re: [GENERAL] Performance
60 secs vs 10 minutes tho! I don't think that can be explained away
with OS
speed differences unless you have the Solaris installation horribly
mangled.
It sounds like the Sparc's test was run on an existing database thats
been
in use...perhaps the indexes need to be cleaned up a little with a
vacuum?
-----Original Message-----
From: Statistical Solutions <statsol@statsol.com>
To: pgsql-general@postgreSQL.org <pgsql-general@postgreSQL.org>
Date: Tuesday, March 30, 1999 9:17 AM
Subject: Re: [GENERAL] Performance
>On Tue, 30 Mar 1999, The Hermit Hacker wrote:
>[snip]
>> Using the rc5 client as a 'benchmark' (what else has programmers
working
>> hard to optimize their code to get the best numbers on it?), we found
that
>> when comparing a Dual-PII 450 against an Sparc E450/400Mhz, the E450
came
>> in at ~30% less powerful then the Dual-PII ...
>>
>> The other thing to consider is that you are comparing two
differences,
not
>> just one. Different CPUs and different operating systems. Solaris
isn't
>> nicknamed 'slowaris' for nothing :) Its a bloated OS, albeit
stable...
>
>The original poster noted using Solaris 2.5.1 -- been there, done that,
it
>certainly can be slow. A long time ago, I contacted Sun about this.
They
>acknowledged a problem with the dynamic library loading routines. I
have
>a Dual Sparc 125/512 running Solaris 2.6 and a dual pentium-100 running
>2.5.1. I'll test some to see if this might be 2.5 v. 2.6 OS
differences,
>although there is stil the underlying hardware issue.
>
>The second point however, is clock speeds. Two 167 CPUs <> One 333
CPU.
>
>The third is the SPARC chip's cache versus the Intel chip's cache. I
know
>SUN and Ross were making chips with as little as 128 cache, and the
SPEC
>marks for the 128 v. 256 v 512 v 1024 cache are phenomenal. So just
out
>of curiousity, what's the cache size on the SPARC and Intel chips
>respectively?
>
>> On Tue, 30 Mar 1999, Jason wrote:
>>
>> > Looking for a little reasoning behind our performance difference on
2
>> > different platforms. We have been running postgres on our sparcs,
and
>> > have come to rely on the dB quite heavily. We have dedicated a box
to
>> > doing nothing but our postgres work. Here is what we have:
>> >
>> > Dual Sparc 167
>> > 512 MB RAM
>> > Solaris 2.5.1
>> >
>> > Performance seemed reasonable to us, until we ran the same database
and
>> > queries on the following machine:
>> >
>> > Intel Celeron 333
>> > 128 MB RAM
>> > Red Hat Linux 5.2
>> >
>> > We have a passwd style database with 65,000 rows. We updated
20,000 of
>> > them with a SQL update command, setting a single integer field to a
>> > value. Both boxes where indexed the same, and had identical data.
The
>> > Sparc took near 10 minutes to complete, while the Intel took ~30
>> > seconds. This is just one case, but many very similar tests had
the
>> > same results.
>> >
