Re: RAID 0 not as fast as expected

From: "Bucky Jordan" <bjordan(at)lumeta(dot)com>
To: "Luke Lonergan" <llonergan(at)greenplum(dot)com>, "Spiegelberg, Greg" <gspiegelberg(at)cranel(dot)com>, "Joshua Drake" <jd(at)commandprompt(dot)com>
Cc: "Craig A(dot) James" <cjames(at)modgraph-usa(dot)com>, <pgsql-performance(at)postgresql(dot)org>
Subject: Re: RAID 0 not as fast as expected
Date: 2006-09-15 18:28:02
Message-ID: 78ED28FACE63744386D68D8A9D1CF5D42099AF@MAIL.corp.lumeta.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-performance

>When we first started working with Solaris ZFS, we were getting about
>400-600 MB/s, and after working with the Solaris Engineering team we
now >get
>rates approaching 2GB/s. The updates needed to Solaris are part of the
>Solaris 10 U3 available in October (and already in Solaris Express, aka
>Solaris 11).

Luke,

What other file systems have you had good success with? Solaris would be
nice, but it looks like I'm stuck running on FreeBSD (6.1, amd64) so
UFS2 would be the default. Not sure about XFS on BSD, and I'm not sure
at the moment that ext2/3 provide enough benefit over UFS to spend much
time on.

Also, has anyone had any experience with gmirror (good or bad)? I'm
thinking of trying to use it to stripe two hardware mirrored sets since
HW RAID10 wasn't doing as well as I had hoped (Dell Perc5/I controller).
For a 4 disk RAID 10 (10k rpm SAS/SCSI disks) what would be a good
target performance number? Right now, dd shows 224 MB/s.

And lastly, for a more OLAP style database, would I be correct in
assuming that sequential access speed would be more important than is
normally the case? (I have a relatively small number of connections, but
each running on pretty large data sets).

Thanks,

Bucky

In response to

Responses

Browse pgsql-performance by date

  From Date Subject
Next Message Benjamin Minshall 2006-09-15 19:12:07 Performance of IN (...) vs. = ANY array[...]
Previous Message Arjen van der Meijden 2006-09-15 16:22:55 Re: Optimize SQL