Re: how to configure my new server

From: eric soroos <eric-psql(at)soroos(dot)net>
To: Curt Sampson <cjs(at)cynic(dot)net>
Cc: pgsql-performance(at)postgresql(dot)org
Subject: Re: how to configure my new server
Date: 2003-02-07 18:06:10
Message-ID: 141418696.1167510126@[4.42.179.151]
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-performance


> > Peaks for striped are @ 80, peaks for single are ~ 100, peaks for
> > mirror are around 100. I'm curious if hw mirroring would help, as I am
> > about a 4 disk raid 5. But I'm not likely to have the proper drives
> > for that in time to do the testing, and I like the ablity to break the
> > mirror for a backup. For comparison, that same system was doing 20-50
> > without the extra 512 stick of ram and on the internal single drive.

Upon some further poking around, I have determined that there were procedural errors that make the data inconsistent. I believe that half of the ram cache may not have been in the state that I thought it was in for all of the tests.

> Hm. That's still very low (about the same as a single modern IDE drive).
> I'm looking for an IDE RAID controller that would get me up into the
> 300-500 reads/writes per second range, for 8K blocks. This should not
> be a problem when doing striping across eight disks that are each
> individually capable of about 90 random 8K reads/writes per second.
> (Depending on the size of the data area you're testing on, of course.)

Running some further tests, I'm seeing software striping in the 125 tps peak/100 sustained range, which is about what I'm getting from the split WAL/Data mode right now. I'm still seeing about 10% reads, so there's probably some more to be gained with additional system ram.

eric

In response to

Browse pgsql-performance by date

  From Date Subject
Next Message Andreas Pflug 2003-02-07 18:42:48 Re: how to configure my new server
Previous Message scott.marlowe 2003-02-07 17:33:48 Re: how to configure my new server