Perl Advocacy Fail

2015-01-16

Guy comes by Perlmonks wondering why his Perl program is so slow to start on a Raspberry Pi. Muses that Perl may be inappropriate for small platforms like this, and that perhaps the program should be rewritten in C. Monks get salty at the thought.

So great, now that guy probably won’t be back.

Now, the program in question was I/O bound, particularly on the Astro::Sunrise module. The initial thought of many Monks was that rewriting in C would not help, but that’s not obvious. Loading the modules involved here is a big task that would be built into a single binary for a C program, plus maybe some shared libraries that will likely be loaded up anyway at boot time.

Even so, there are better ways of helping here. The program uses threads and Switch, which are both probably unnecessary. Using threads in particular is a big performance suck.

I also double-checked, and the default perl on Raspbian actually is compiled with threads. I’m sure that’s because the base Debian distro has to be compatible with any Perl script you throw at, but that’s a big, unnecessary performance suck for a little Rpi. I’ll have to check, but Hiveberry might have a more sensible compile of perl. It’s a more up-to-date 5.20, as well (Raspbian comes with 5.14). That could make for a nice performance boost.