OpenJDK ARM build not using all the CPU cores

[Mani Sarkar]

Thanks Erik, I have updated our scripts with this flag.

Cheers,
Mani

On Wed, 19 Apr 2017 at 10:29 Erik Joelsson <erik.joelsson at oracle.com> wrote:

> If you want to do the override at configure time, the correct configure
> parameter is --with-jobs=4. The --with-num-cores isn't all that useful
> except for easier testing of the logic for calculating the default
> number of jobs (which is why I left it there).
>
> The default limitation of jobs based on memory is rather conservative (1
> job per 1024MB IIRC). We don't like to assume that building is the only
> thing the system ever does. Also most of the build tasks aren't that
> memory hungry, but some are. I recommend you try manually increasing
> jobs until you find your optimal level of concurrency for the types of
> builds you do.
>
> /Erik
>
>
> On 2017-04-19 11:07, Ioi Lam wrote:
> > If you really want, you can override the settings with
> >
> > make JOBS=4 images
> >
> > Of course, YMMV due to the low amount of memory.
> >
> > Ioi
> >
> >> Mani Sarkar <sadhak001 at gmail.com> 於 2017年4月19日 下午4:07 寫道：
> >>
> >> Thanks Andrew for clarifying.
> >>
> >>> On Wed, 19 Apr 2017 at 08:56 Andrew Haley <aph at redhat.com> wrote:
> >>>
> >>>> On 19/04/17 08:42, Mani Sarkar wrote:
> >>>> Whilst build OpenJDK (latest version from
> >>>> http://hg.openjdk.java.net/jdk8u/jdk8u/), we have noticed, that the
> >>> build
> >>>> system does not make use of all the CPU cores available on the machine
> >>> even
> >>>> though it detects them all.
> >>> It's because you have almost no memory installed.  If you want to
> >>> override the number of cores to use you can do so manually, but the
> >>> idea is to prevent you from running out of memory during the build.
> >>> It's deliberate, not a bug.
> >>>
> >>> Andrew.
> >>>
> >>> --
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