Re: Add on_perl_init and proper destruction to plperl [PATCH]

On Wed, Jan 27, 2010 at 11:28:02AM -0500, Tom Lane wrote:
> Andrew Dunstan <andrew@dunslane.net> writes:
> > Tom Lane wrote:
> >> Indeed, AFAICS the major *point* of these additions is to allow people
> >> to insert unknown other functionality that is likely to interact
> >> with the rest of the backend; a prospect that doesn't make me feel
> >> better about it.
> 
> > No. The major use case we've seen for END blocks is to allow a profiler 
> > to write its data out. That should have zero interaction with the rest 
> > of the backend.
> 
> Really?  We've found that gprof, for instance, doesn't exactly have
> "zero interaction with the rest of the backend" --- there's actually
> a couple of different bits in there to help it along, including a
> behavioral change during shutdown.  I rather doubt that Perl profilers
> would turn out much different.

Devel::NYTProf (http://blog.timbunce.org/tag/nytprof/) has zero
interaction with the rest of the backend.

It works in PostgreSQL 8.4, although greatly handicapped by the lack of
END blocks. http://search.cpan.org/perldoc?Devel::NYTProf::PgPLPerl

> But in any case, I don't believe for a moment that profiling is the only
> or even the largest use to which people would try to put this.

Can you give any examples?

Tim.