question about Rpvm, SNOW, etc.
A.J. Rossini
rossini@u.washington.edu
20 Aug 2002 12:53:09 -0700
>>>>> "michael" == Michael Na Li <lina@u.washington.edu> writes:
michael> I got similar timing with our cluster. Saving and loading the object to/from
michael> a file require about 1.5 seconds each, which I assume is the cost of the
michael> serialization (plus file reading and writing). Then it seems the packing (as
michael> bytes), transferring, and unpacking the object take 7-8 seconds??
michael> I wonder how much the serialization itself hurts the performance. Would
michael> sending raw numbers with pvm routines improve the performance?
It might. It is "well-known" that PVM (and MPI, and other
message-passing systems) have a marshalling overhead that can be
easily beat by RPC or direct socket programming. This suggests that
the lower/rawer the data at the message passing stage, the faster it
might be.
best,
-tony
--
A.J. Rossini Rsrch. Asst. Prof. of Biostatistics
U. of Washington Biostatistics rossini@u.washington.edu
FHCRC/SCHARP/HIV Vaccine Trials Net rossini@scharp.org
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