[petsc-dev] [Ideas-team] Seeking OLCF users complaining about poor build times

Todd Gamblin tgamblin at llnl.gov
Fri Feb 27 10:49:34 CST 2015


On 2/27/15, 8:45 AM, "Satish Balay" <balay at mcs.anl.gov> wrote:

>On Fri, 27 Feb 2015, Todd Gamblin wrote:
>
>Its just that users won't think of doing this.  [also we usually
>default to inplace build - and use /tmp for build - works well with
>--prefix install].

Yes exactly.  Users are used to running curl -O (if that) in their home
directory and building there.  So it is kind of sad that the home
directory is not optimized for compiles.

>Also I think such usage at LC centers might be prohibited.  And some
>systems are configured in such a way that /tmp is really not useful
>for source builds. [For eg - configure tends to do simpile runs - that
>get blocked due to security settings on /tmp]

Why would it be prohibited?  Especially if you remove the build after it's
done?  What's a "simple run" and why do the security settings prohibit it?

I do not think LC (Livermore Computing -- maybe I shouldn't use that
acronym here?) does this.

-Todd


>
>Satish
>
>> 
>> -Todd
>> 
>> 
>> 
>> On 2/27/15, 8:09 AM, "David E. Bernholdt" <bernholdtde at ornl.gov> wrote:
>> 
>> >Barry, thanks, this is extremely helpful.  I'll have the OLCF folks
>> >contact Nathan if they need any further info or have other experiments
>> >to try.
>> >
>> >On 02/27/2015 11:03 AM, Barry Smith wrote:
>> >> 
>> >>   Same text also in the attachment.
>> >> 
>> >>    Barry
>> >> 
>> >> David,
>> >> 
>> >>     Nathan Collier has kindly run a test on Titan, Satish on Mira and
>> >>Hopper, and Victor on Ranger with a basic optimized build of PETSc
>>(all
>> >>C code)
>> >> 
>> >>     Please find below some configure and make timings from the latest
>> >>PETSc master.
>> >> 
>> >>      The Titan times for both configure and make are unacceptable.
>>For
>> >>total build time Titan is 3.5 times slower than Mira and Hopper and at
>> >>least 10 times slower than laptops. The "time" results on Titan are
>> >>disturbing
>> >> 
>> >> configure 
>> >> real	14m32.169s   (since the user + sys time is much less than real
>> >>time, what is it waiting on?)
>> >> user	1m51.527s
>> >> sys	3m40.734s
>> >> 
>> >> make
>> >> real	15m56.004s
>> >> user	8m8.971s
>> >> sys	52m42.734s  (why so much?)
>> >> 
>> >> which I read as either the filesystem or the compiler system
>>(location
>> >>of the compilers, license server of the compilers, ...) is really
>>badly
>> >>configured.
>> >> 
>> >>    The Hopper configure time with the default
>> >>TMPDIR=/scratch/scratchdirs/balay is is unacceptable but if you
>>actually
>> >>use the real /tmp it becomes somewhat reasonable.
>> >> 
>> >> Feel free to share this information with local experts,
>> >> 
>> >>   
>> >> 
>> >> 
>> >> I suggest you view the below table in a fixed width font editor like
>> >>Emacs or Vi so the columns line up.
>> >> 
>> >>                     configure time    make time   Total
>>compilers
>> >>   filesystem
>> >> 
>> >> Titan                14m32s         15m56s        30m28s      Intel
>>14
>> >>  /lustre/atlas1/geo103/proj-shared/
>> >>                      41m38s          9m5s         50m43s
>> >> /ccs/home/  (no load on login node)
>> >> 		     13m   
>> >>(no load on a different login node)
>> >> 
>> >> Mira                  6m59s          1m49s         8m48s       IBM
>> >>  /gpfs/mira-home/
>> >> 
>> >> Hopper               23m17           1m45s        25m2s
>> >>  /global/u2/b/balay/petsc.clone default
>> >>TMPDIR=/scratch/scratchdirs/balay
>> >> 		      6m17s          1m39s         7m57s                   manually
>> >>set TMPDIR=/tmp
>> >> 
>> >> NSF Ranger UT Austin  5m10s          1m28s         6m38s
>> >>     default, whatever it is
>> >> 
>> >> Linux laptop            53s          1m13s         2m6s         Gnu
>> >>      compile and compiler local
>> >> 
>> >> Apple laptop          1m14s            54s         2m8s         clang
>> >>      compile and compiler local
>> >> 
>> >> Linux workstation     1m11s            22s         1m33s        Gnu
>> >>    compile and compiler local
>> >>                       1m37s            29s         2m6s         Gnu
>> >>    compile directory local; compiler directory remote
>> >>                       3m11s            25s         3m36s       Intel
>>13
>> >>    compile directory local; compiler directory remote
>> >> 
>> >> PETSc has about 1000 source files that need compiling
>> >> 
>> >> The configure is essentially sequential, the make extremely parallel.
>> >> 
>> >> During configure the source code is on the listed file system, all .o
>> >>and executables  are on /tmp
>> >> 
>> >> During the make the source code and all .o are on the listed file
>>system
>> >> 
>> >> 
>> >>> On Feb 25, 2015, at 11:23 AM, David E. Bernholdt
>> >>><bernholdtde at ornl.gov> wrote:
>> >>>
>> >>> At the kick-off meetings, one of the general complaints I heard
>> >>> expressed about the facilities was the slow build times compared to
>> >>> personal systems.
>> >>>
>> >>> If you have this complaint and are an OLCF user, and are willing to
>> >>>work
>> >>> with us a little to try to understand your experience in more
>>detail,
>> >>> please contact me (individually, not reply-all).
>> >>>
>> >>> This is a facility thing, not an IDEAS thing, so I can't speak for
>>the
>> >>> other facilities.  But we've recently received some other similar
>> >>> comments, and we're trying to dig into what's happening.
>> >>>
>> >>> Thanks
>> >>> -- 
>> >>> David E. Bernholdt                | Email: bernholdtde at ornl.gov
>> >>> Oak Ridge National Laboratory     | Phone: +1 865-574-3147
>> >>> http://www.csm.ornl.gov/~bernhold | Fax:   +1 865-576-5491
>> >>> _______________________________________________
>> >>> Ideas-team mailing list
>> >>> Ideas-team at lists.mcs.anl.gov
>> >>> https://lists.mcs.anl.gov/mailman/listinfo/ideas-team
>> >
>> >
>> >-- 
>> >David E. Bernholdt                | Email: bernholdtde at ornl.gov
>> >Oak Ridge National Laboratory     | Phone: +1 865-574-3147
>> >http://www.csm.ornl.gov/~bernhold | Fax:   +1 865-576-5491
>> >_______________________________________________
>> >Ideas-team mailing list
>> >Ideas-team at lists.mcs.anl.gov
>> >https://lists.mcs.anl.gov/mailman/listinfo/ideas-team
>> 
>> 
>> 
>





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