Re: Slow count(*) again...

Dan Harris wrote:
> I'm not sure how to figure out what version of XFS we're on.. but it's
> Linux kernel 2.6.24-24 x86_64 on Ubuntu Server 8.04.3. Postgres
> version 8.3

There's the kernel side support that matches your kernel, as well as the
xfsprogs package. The latter is where a lot of distributions haven't
kept up with upstream changes, and where I suspect the defragmenter bug
you ran into is located at.

Hardy ships with 2.9.4-2: http://packages.ubuntu.com/hardy/xfsprogs

The work incorporating a more stable XFS into RHEL started with xfsprogs
3.0.1-6 going into Fedora 11, and 3.1.X would represent a current
release. So your Ubuntu kernel is two major improvement releases
behind, 3.0 and 3.1 were the upgrades to xfsprogs where things really
got going again making that code modern and solid. Ubuntu Lucid
switched to 3.1.0, RHEL6 will probably ship 3.1.0 too.

--
Greg Smith, 2ndQuadrant US greg(at)2ndQuadrant(dot)com Baltimore, MD
PostgreSQL Training, Services and Support www.2ndQuadrant.us
Author, "PostgreSQL 9.0 High Performance" Pre-ordering at:
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