Re: [gentoo-user] emerge -j, make -j and make -l

[Pandu Poluan <pandu@poluan.info>]

[-- Attachment #1: Type: text/plain, Size: 2109 bytes --]

On Nov 28, 2011 11:38 AM, "Michael Mol" <mikemol@gmail.com> wrote:
>
> On Sun, Nov 27, 2011 at 7:54 PM, Pandu Poluan <pandu@poluan.info> wrote:
> >
> > On Nov 28, 2011 6:24 AM, "Neil Bothwick" <neil@digimed.co.uk> wrote:
> >>
> >> On Mon, 28 Nov 2011 00:56:17 +0700, Pandu Poluan wrote:
> >>
> >> > I don't know where the 'blame' lies, but I've found myself
> >> > standardizing on MAKEOPTS=-j3, and PORTAGE_DEFAULT_OPTS="--jobs
> >> > --load-average=<1.6*num_of_vCPU>"
> >> >
> >> > (Yes, no explicit number of jobs. The newer portages are smart
enough to
> >> > keep starting new jobs until the load number is reached)
> >>
> >> The problem I found with that is the ebuilds load the system lightly to
> >> start with, before they enter the compile phase, to portage starts
dozens
> >> of parallel ebuilds, then the system gets completely bogged down when
> >> they start compiling.
> >>
> >
> > Yes, sometimes that would happen if at the beginning there are
network-bound
> > ebuilds all downloading their respective distfiles. The load stays low
until
> > they all start ./configure-ing roughly at the same time. Then all hell
> > breaks loose.
> >
> > I successfully mitigate such "load-explosion" by doing a --fetchonly
step
> > first, and keeping MAKEOPTS at low -j (which, in my case, is actually
> > required).
> >
> > Just to add more info: I use USE=graphite (with some CFLAGS, uh,
> > 'enhancements') with gcc-4.5.3. IIRC, I could push MAKEOPTS up to -j5
(and
> > even more, but I ran out of cores) when I was still using gcc-4.4.x and
no
> > USE=graphite.
> >
> > Won't file a bug report, though. I have a feeling that my bug report re:
> > emerge failure will be marked WONTFIX thanks to the 'ricer special'
CFLAGS
>
> As I noted, "-l" in MAKEOPTS takes care of the load explosion very nicely.

Most likely so. I am not aware of -l in MAKEOPTS before, so what I posted
was my workaround to prevent load explosion. Thanks to your very useful
tip, I now no longer have to worry about load explosion :-)

(I still like doing pre-fetchonly-ing, though. But now for a different main
reason :-)

Rgds,

[-- Attachment #2: Type: text/html, Size: 2805 bytes --]