Re: [GENERAL] Performance - Mailing list pgsql-general

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 ...
>
> If you take a look at http://infopad.EECS.Berkeley.EDU/CIC/summary/local,
> it shows comparisons of the various CPUs out there, up until Nov/98 ...
> the Intel CPUs blow away the Sparc chip's in integer arithmetic, while the
> Sparc excels in floating point.  Your operating system, and the database,
> tends to do most stuff in integer, so you get performance boons that
> way...
>
> 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.
> >
> > Now I love Linux, and the price compared to a Sparc makes it much
> > simpler to get one on line.  However, I can't understand why the Sparc
> > would lag so far behind.  We are starting Postgres the same on both
> > machines:
> >
> > su - postgres -c "/usr/local/pgsql/bin/postmaster -B 256 -o -F -i -S"
> >
> > We are looking at getting a dual 400 Intel Pentium II box with Red Hat
> > to migrate all of the Postgres work to.  But in the meantime, is there a
> > way to optimize the performance on the Sparc?  Thanks in advance.
> >
> > -Jason Neumeier.
> >
> >
> >
>
> Marc G. Fournier                   ICQ#7615664               IRC Nick: Scrappy
> Systems Administrator @ hub.org
> primary: scrappy@hub.org           secondary: scrappy@{freebsd|postgresql}.org
>
>
>