Re: Perl v5.6.1 looking for .pmc files

[fglock]

in reply to Perl v5.6.1 looking for .pmc files

From: http://dev.perl.org/perl5/list-summaries/p5p-200207-3.pod.html

.pmc files

Nick Ing-Simmons found an old, unused feature that was deeply burried into the perl code : when loading a module via use or require, perl checks whether there's a .pmc file along the .pm file, and newer; if it finds it, it gets loaded in place of the .pm. This was intended to be used by the byteloader, but apparently isn't used at all (unless something was missed.) Anyway it was too late to remove it.

http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/2002-07/msg00555.html

[ruscoekm]

Ha! Many thanks for digging that one out of the archives. Nick's comment that "The required stat()s on a sick NFS system are significant!" summed up my feelings exactly :-)

By the sound of the subsequent mail chain, there should be a workaround in v5.8.1. Until then, I guess I will have to look for improvements elsewhere.

Cheers, Kevin

[DapperDan]

Bravo for finding this!

I too wondered what the flap was with these .pmc stat calls, because the original question was well-asked.

[rvosa]

Sooo... instead you could speed things up by compiling the modules to bytecode using Module::Compile (okay, in theory).

[fglock]

yes! except that the feature is more used nowadays to preprocess complex code into plain perl5, instead of bytecode. v6, for example, process perl6 source code into plain perl5 "pmcs".