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1 reply Latest Post - ‏2014-07-01T07:32:38Z by NLai
SystemAdmin
SystemAdmin
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Pinned topic Performance problem with PS3

‏2013-02-22T17:55:39Z |
Hi

I am currently using a PS3 to do a series of matrix inversions using the CELL LAPACK routines.

See the attached file where I am inverting a 1000x1000 DP matrix using DPOTRF and DPOTRI which takes 2 seconds to complete using 6 SPES (LAPACK_NUMSPES=6) as opposed to a runtime of 0.8 seconds in my Pentium 4 3.4Ghz. When I run the command 'spu-top' I see the 6 SPUs at 100% while the program is running.

I used the Makefile provided with the CELLSDK3.1 and this program compiles without any warnings nor errors.

I tried both SP and DP cases and the Pentium 4 running on 1 thread beats the CELL for any matrix size.

Why is the performance so low??

Thank you in advance

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  • NLai
    NLai
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    Re: Performance problem with PS3

    ‏2014-07-01T07:32:38Z  in response to SystemAdmin

    I wonder you might need to take advantages of Cell's 128 of 128-bit vector registers and reduce the use of LOOP statements in favor of parallel programming.

    I have all modern Intel and AMD built, no one comes close to the Cell in my PS3 core-to-core; Intel is OK, but the 6-cores AMD is not only poor in a single core performance, but also running very very hot like a heater, better to run it in winter.

    I would suggest IBM make another round of PC, this time call it SPC for Super PC using a version of the Cell processor to target university professors and learners, since they would have never found the Cell processor "difficult to program" like what Sony did,

    thanks.