memxfer: a simple benchmark for memory transfer

memxfer (jj version)

With memxfer you can compare the memory transfer performance between

copying techniques like the strcpy vs. copying integers or doubles.
machines (in case you can access them)
BIOS settings
copying with or without unrolling and prefetching

Included are assembler inlines (for the AMD athlon and AMD64) that use non-temporal copying instructions (movntq).

Get the source code here: memxferjj.cc. Notes on how to compile and run the code are at the beginning of the file. There is also a makefile.

Sample output files: memxferjj-out.txt (different AMD athlon systems 1333/1800, SDRAM/DDR and CAS-latencies 2.5/2) and memxferjj-test.txt (various BIOS settings of one AMD athlon system)
memxferjj-amd64-out.txt (AMD64 2.2GHz, socket 939, dual channel DDR memory at 200MHz). Note how fast the memcpy() routine is (first to blocks). The third and fourth block suggest that the streaming routine should not be used for blocks of small size. The executable used is memxferjj.

Your feedback is appreciated.

jj (Jörg Arndt)

Last modified 2009-March-11 (09:28)

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