[MLton] self-compile blues

[Filip Pizlo]

> It seems slow.  But I haven't run MLton built by the C codegen in a
> while.  The usual rule of thumb is it's a factor of two slower than
> the native codegen.  Factoring everything in and making a wild guess,
> I'd think you could do the pre codegen in under 20 minutes.

Out of curiosity, what optimization level do you usually compile the C
code with?  I compiled with -Os, which is the "Apple recommended" level
(it's sorta like -O2 but does more space optimization, if I remember
correctly).

> > 1) How much memory does a self-compile really need?
> 
> You might be able to squeeze by with a heap size of 512M.
> 
> > 2) What, exactly, does ram-slop affect?  Is it only the GC'd heap, or is
> > the whole size of the process taken into account?
> 
> ram-slop is multiplied by the total RAM size to get the maximum size
> of the GC'd heap.  It doesn't take anything else into account.
> 
> You could also use fixed-heap 600m (or whatever size) instead of
> ram-slop, since we're experimenting.

Thanks for the info.  I'll let this build finish just so that I have a
number on how long it took.  Then I'll try some other settings.

--
Filip Pizlo
http://bocks.psych.purdue.edu/
pizlo@purdue.edu