Memory needed to build Perl 6 on Parrot; problem, goal, incentive for solution

[Andy Dougherty]

On Sun, 1 Aug 2010, James E Keenan wrote:

> 1.  Problem.
> 
> Last week I successfully built Rakudo Star from source on two different
> Linux/i386 machines, one real, one virtual.  However, my attempt to build
> Rakudo Star on my iBook was unsuccessful.  It repeatedly failed at this point:
> 
>   /Users/jimk/work/rstar/rakudo-star-2010.07/install/bin/parrot
> src/gen/perl6.pbc --target=pir \
>     src/gen/core.pm > src/gen/core.pir
> 
> I filed an RT for this: http://rt.perl.org/rt3//Ticket/Display.html?id=76828.
> 
> In the course of discussion in that ticket, I noted that I had been able to
> build Perl 6 on top of Parrot on that same machine at least as late as June
> 2008, when I led a workshop to do that at YAPC::NA in Chicago. Coke responded
> that the file where compilation failed was "the single largest compilation
> that occurs during the process, and requires a LOT of memory, and it's likely
> gotten bigger since the last time you ran." I have 256 MB of physical memory
> available on this machine, to which Coke responded, "Based on recent history,
> I think 1G is the minimum recommend memory for building rakudo (for that file
> in particular)."

This matches my experience.  I have not been able to build rakudo on
my Solaris 8/SPARC system for quite some time, and, more recently,
have usually not been able to build it on my OpenSolaris/x86 system
either.

The main culprits in parrot's recent history appear to be "immutable
strings" and StringBuilder.  I seem to recall a flurry of activity
when building rakudo crossed the 1 GB limit.  Also, pbc_to_exe for
non-gcc compilers often causes out-of-memory issues for me, but isn't
an issue for Darwin.

> 3.  Disposal of Red Herring; A Bit of History.
> 
> To be frank, one approach would be to say, "kid51, your iBook is six years old
> -- ancient in computer years.  You're the only one still submitting smolder
> tests for Darwin/PPC.  Go out and buy a new one and throw that G4 away."
> 
> You could say that, but of course I would not do that.  I am tempermentally
> the kind of person who keeps hardware running as long as possible.

Many potential users of rakudo are in the same boat.  They try to run
on what hardware they have, and may not have a budget to do anything
else.

I like your proposed incentive.  It's a very positive, specific
proposal, presented in a very constructive way.  Good luck with it!

-- 
    Andy Dougherty		doughera at lafayette.edu