[Dbix-class] Why is prefetch so slow?

[Matt S Trout]

On Thu, Oct 18, 2007 at 03:03:24PM +0930, Jon Schutz wrote:
> On Wed, 2007-10-17 at 16:19 +0100, Nigel Metheringham wrote:
> > Jon,
> > 
> > You should look at RH bug #196836 for information on the Red Hat
> > perl bug that causes this.
> > 
> > https://bugzilla.redhat.com/show_bug.cgi?id=196836
> > 
> 
> Interesting, well found.
> 
> As background for those who missed yesterday's IRC discussion, it was
> identified that the original slow-down problem was specific to CentOS 5
> standard perl-5.8.8-10 RPM (and presumably all other distributions using
> the same).
> 
> According to the bug report above, the problem should be fixed in RPM
> perl-5.8.8-22 and later, so I compiled and installed perl-5.8.8-24 and
> re-ran Nigel's benchmark.  The results show that the patched patched
> version in 5.8.8-24 is still about 2-4 as slow with/without my patch to
> ResultSourceHandle.  This compares against 8-12 times slower with
> perl-5.8.8-10.

Would you concur that in that case this doesn't justify modifying DBIx::Class'
code to compensate?

Do you reckon a warning or just a note in the documentation is in order to
warn people using broken RH perls to compile their own for best performance?

-- 
      Matt S Trout       Need help with your Catalyst or DBIx::Class project?
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