Re: Out of memory while building GCC 12.1.0

[Paul Smith <paul@mad-scientist.net>]

On Fri, 2022-06-10 at 15:29 +0300, Fiodar Stryzhniou wrote:
> > If you don't set that variable it will try to compile every file at
> > once. Either set the variable, or fix your script to use a sensible
> > default like -j"${NUMBER_OF_PROCESSORS:-1}"
> 
> Looks like you right. Harcoded to -j6 helps.

Another way to go is to add the "-l" option.  This is often combined
with "-j" (no limit) to have your build limited by load rather than by
job count.

So if you want the load on your system to be no greater than 2, you can
say "-j -l2".

Just to be aware, on Linux a load of "1" means approximately "1 CPU is
100% busy".  So if you use "-l2" then you'll likely have between 2 and
3 jobs running, but if your jobs have to do a lot of waiting (say they
need to do a lot of disk IO / your disk is slow) then you will have
more running.

Anyway, getting the best behavior out of parallelism is a matter of
trial and error and is specific to your build environment.  But plain
"-j" with no other control is virtually never a good idea :).