[MITgcm-support] bluesky build

[Ed Hill]

On Tue, 2005-06-07 at 11:25 -0400, Mike Spall wrote:
> Hi All,
> 
> I have tried compiling MITgcm on ncar's bluesky.  It seems
> to be working in that I get no errors, but it also seems
> to be taking a very long time.  I compiled with 
> MITgcm/tools/build_options/sp4+mpi yesterday and
> it was not done after > 20 minutes so I killed it.
> I was doing this interactively, not by batch.
> Does this sound right?

Hi Mike,

This is only a guess, but it sounds like the very slow build could be
due to slow disk I/O.  Please contact the bluesky admins since there is
almost nothing that we can do about it from our side.

Also, if you are doing a build on an SMP system and you have access to
Gnu make ("gmake") or a similarly capable "make", then you can do the
following:

  ../../../tools/genamke2 ...OTHER_OPTIONS...
  make depend
  make -j 4

where the "-j 4" specifies that four jobs should be run in parallel.  On
SMP systems, this can result in huge speedups of the build.  For
instance, "-j 3" on dual-processor Opterons and "-j 16" on some Altix
systems can provide massive (approximately, x2 and x14) speedups of the
compilation stage.

Ed

-- 
Edward H. Hill III, PhD
office:  MIT Dept. of EAPS;  Rm 54-1424;  77 Massachusetts Ave.
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