[petsc-dev] could we let "make -j N" work for PETSc and external packages?

[Satish Balay]

With what compilers? Is this license issue - or RAM issue? [i.e what
errors do you get?]

If your compiler fails this way - its likely to affect externalpackage
builds aswell. So you might need to use configure option:

--with-make-np=1

[But I would think a value higher than 1 should work..]

Satish

On Wed, 25 Jul 2018, Fande Kong wrote:

> The default value determined by the configure sometimes makes the compiling process fail.  I have experienced a couple of times before. The solution is to use "MAKE_NP=1".
> 
> 
> 
> Fande,
> 
> 
> ________________________________
> From: petsc-dev <petsc-dev-bounces at mcs.anl.gov> on behalf of Satish Balay <balay at mcs.anl.gov>
> Sent: Tuesday, July 24, 2018 5:57:55 PM
> To: Fande Kong
> Cc: petsc-dev
> Subject: Re: [petsc-dev] could we let "make -j N" work for PETSc and external packages?
> 
> Another alternative: use gmakefile directly - and ignore our
> 'makefile' wrapper.
> 
> [with makefile wrapper - we try to control a few things - and print
> some extra debug info like the MAKEFLAGS].
> 
> But if you use 'gmakefile' directly - you would be using PETSc like
> any other package - it supports 'V=1' for some debug info [which is
> similar to info provided by most packages]
> 
> 
> BTW: Any particular why MAKE_NP determined by configure [i.e the default value] is not useful?
> 
> Satish
> 
> On Tue, 24 Jul 2018, Fande Kong wrote:
> 
> > Thanks, Satish,
> >
> > I’m going to use MAKE_NP
> >
> > Fande
> >
> > Sent from my iPhone
> >
> > > On Jul 24, 2018, at 4:26 PM, Satish Balay <balay at mcs.anl.gov> wrote:
> > >
> > > I hate html e-mail which doesn't add reply markers - can't figure out easily what you saying :(
> > >
> > >>> However some older make version might not display this info properly. [it should use the user specified '-j' value though]
> > >>
> > >> This confused me, and now I understood.  But it is misleading. Could we do something at the PETSc side regardless the make version? At least display the user-specified value not the default value.  I thought my "-j" did not change anything.
> > >
> > > Thats a 'make' issue. you are specifying options to make. So we have no control on it [unless make tells us - and this mode is buggy on the OSX default make version].
> > >
> > > The only option we have is : not print anything. I think thats a bad option.
> > >
> > > You have alternatives:
> > >
> > > - use a newer make with --download-make
> > >
> > > - or use MAKE_NP
> > >
> > > Satish
> > >
> > >> On Tue, 24 Jul 2018, Fande Kong wrote:
> > >>
> > >>
> > >>
> > >>
> > >> ________________________________
> > >> From: Satish Balay <balay at mcs.anl.gov>
> > >> Sent: Tuesday, July 24, 2018 4:06 PM
> > >> To: Fande Kong
> > >> Cc: Jed Brown; For users of the development version of PETSc
> > >> Subject: Re: [petsc-dev] could we let "make -j N" work for PETSc and external packages?
> > >>
> > >> PETSc configure sets up a default value that always gets used.
> > >>
> > >>>>>>>>>
> > >> balay at asterix /home/balay/tmp/petsc (maint=)
> > >> $ make
> > >> <snip>
> > >> Using MAKEFLAGS: -j4 -l6.0 w -- PETSC_DIR=/home/balay/tmp/petsc PETSC_ARCH=arch-linux2-c-debug
> > >> <<<
> > >>
> > >> You can always override this default by adding a -j option. [since the
> > >> user specified -j value comes at the end - it overrides the one that
> > >> is specified at the begining of make command]
> > >>
> > >>>>>>>>>>>>
> > >> balay at asterix /home/balay/tmp/petsc (maint=)
> > >> $ make -j20
> > >> <snip>
> > >> Using MAKEFLAGS: -j4 -l6.0 w -j20 --jobserver-auth=3,4 -- PETSC_DIR=/home/balay/tmp/petsc PETSC_ARCH=arch-linux2-c-debug
> > >> <<<<<<<<<<
> > >>
> > >>
> > >> However some older make version might not display this info properly. [it should use the user specified '-j' value though]
> > >>
> > >> This confused me, and now I understood.  But it is misleading. Could we do something at the PETSc side regardless the make version? At least display the user-specified value not the default value.  I thought my "-j" did not change anything.
> > >>
> > >> Fande,
> > >>
> > >>>>>>>>>
> > >> [petsc at ipro petsc.maint ((879a78556f...))]$ make -j2
> > >> Using MAKEFLAGS: -j7 -l12.0 w --jobserver-fds=3,4 -j -- PETSC_DIR=/Users/petsc/petsc.maint PETSC_ARCH=arch-osx-10.6
> > >> <<<<<<<
> > >>
> > >> You can use the alternate mode - just modify the default '-j' value used MAKE_NP
> > >>
> > >>>>>>>>>>
> > >> [petsc at ipro petsc.maint ((879a78556f...))]$ make MAKE_NP=2
> > >> Using MAKEFLAGS: -j2 -l12.0 w -- PETSC_DIR=/Users/petsc/petsc.maint PETSC_ARCH=arch-osx-10.6 MAKE_NP=2
> > >> <<<<<<<
> > >>
> > >> Or you can control this default value at configure time [this affects externalpackage builds]
> > >>
> > >> ./configure --with-make-np=2
> > >>
> > >> Satish
> > >>
> > >>
> > >>> On Tue, 24 Jul 2018, Fande Kong wrote:
> > >>>
> > >>> Thanks, Jed and Satish,
> > >>>
> > >>>
> > >>> But "make -j N" does not change anything when compiling petsc.
> > >>>
> > >>>
> > >>>
> > >>> If I do something like: "make -j whatever". Then I always get:
> > >>>
> > >>>
> > >>> Using MAKEFLAGS: -j8 -l36.0 w
> > >>>
> > >>>
> > >>> It looks like PETSc always uses "-j something" that we can not change using the command-line.
> > >>>
> > >>>
> > >>> Is it a bug?
> > >>>
> > >>>
> > >>>
> > >>> Fande,
> > >>>
> > >>>
> > >>>
> > >>> ________________________________
> > >>> From: Jed Brown <jed at jedbrown.org>
> > >>> Sent: Tuesday, July 24, 2018 3:44 PM
> > >>> To: Fande Kong; For users of the development version of PETSc
> > >>> Subject: Re: [petsc-dev] could we let "make -j N" work for PETSc and external packages?
> > >>>
> > >>> Fande Kong <Fande.Kong at inl.gov> writes:
> > >>>
> > >>>> Hi Developers,
> > >>>>
> > >>>>
> > >>>> Could we somehow let "make -j N" to take multiple threads for compiling PETSc. Do we use multiple threads when compiling the external packages such as hypre, parmetis etc.?
> > >>>
> > >>> Yes, see self.parallelMake=0 for the few packages that don't support parallel make.
> > >>>
> > >>
> > >>
> > >
> >
>