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The Grumpy Editor goes 64-bitThe Grumpy Editor goes 64-bitPosted Apr 15, 2004 14:41 UTC (Thu) by evgeny (subscriber, #774)Parent article: The Grumpy Editor goes 64-bit One more thing. Regarding the 64- vs 32-bit performance. Of course, one shouldn't expect big difference for 32-bit apps (I mean those manipulating 32-bit integers and floats) - not without some genuine magic inside processor and/or compiler at least. But with long longs and doubles, the difference should be impressive in most cases. My own numbercrunching codes (using doubles) jump exactly twice in productivity when going to 64 bits. Or, compare user time of md5sum ran over a large (e.g. an ISO image) file. As far as the amd64 arch is considered, one should realize that its direct competitor (before Intel announced its "own" x86_64), P4/Xeon4 is nothing but braindamaged multimedia-oriented castrated PIII. The only runner-up is Centrino but finding a SMP Centrino box is not a trivial task ;-). Plus, GHz of AMD are higher. So, even compiled for x86_32 (if e.g. one is bound to a commercial 32bit-only compiler) computational-intensive sci apps should significantly outperform when run on amd64.
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The Grumpy Editor goes 64-bit Posted Apr 15, 2004 16:24 UTC (Thu) by ewan (subscriber, #5533) [Link] For floating point number crunching an Itanium is a more obviouscompetitor than a Xeon and will confortably outperform an Opteron even though running at a lower clock rate.
The Grumpy Editor goes 64-bit Posted Apr 15, 2004 16:35 UTC (Thu) by evgeny (subscriber, #774) [Link] Itanium is in the different price domain. As to performance, I triedItanium-1 and wasn't impressed. Probably Itanium-2 is different.
The Grumpy Editor goes 64-bit Posted Apr 17, 2004 5:20 UTC (Sat) by ksmathers (subscriber, #2353) [Link] As to performance, I tried Itanium-1 and wasn't impressed. Probably Itanium-2 is different.Certainly I2 is improved, but not that much. A disadvantage of EPIC is that if your compiler isn't really good at optimizing for the instruction set, the CPU will spend most of its time idle. Itanium performance depends very heavily on being able to keep the instruction lines full, and since there is no intelligence in the CPU at all, it is up to the compiler to accomplish that parallelism. Itanium can beat any other CPU out there, but without the parallelism afforded by an extremely customized compiler backend, it can also feel like molasses.
The Grumpy Editor goes 64-bit Posted Apr 17, 2004 22:06 UTC (Sat) by dvdeug (subscriber, #10998) [Link] The AMD64 doubles the number of general purpose registers. That may cause a big difference for some 32-bit apps.
The Grumpy Editor goes 64-bit Posted Apr 27, 2004 0:34 UTC (Tue) by barrygould (guest, #4774) [Link] You must compile your apps into 64-bit binaries in order to get access to the extra registers.A 32-bit binary won't be able to use them.
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