[petsc-dev] [GPU] Performance on Fermi

[Barry Smith]

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  You need to build the code with ./configure --with-debugging=0 to make a far comparison. This will speed up the CPU version.

   Barry


On Aug 27, 2010, at 2:22 PM, Keita Teranishi wrote:

> Barry,
> 
> CPU version takes another digit. So it is 1.6 sec on Fermi and 17 sec 1 core CPU.
> 
> Thanks,
> ================================
>  Keita Teranishi
>  Scientific Library Group
>  Cray, Inc.
>  keita at cray.com
> ================================
> 
> 
> -----Original Message-----
> From: petsc-dev-bounces at mcs.anl.gov [mailto:petsc-dev-bounces at mcs.anl.gov] On Behalf Of Keita Teranishi
> Sent: Friday, August 27, 2010 2:20 PM
> To: For users of the development version of PETSc
> Subject: Re: [petsc-dev] [GPU] Performance on Fermi
> 
> Barry,
> 
> Yes. It improves the performance dramatically, but the execution time for KSPSolve stays the same.
> 
> MatMult 5.2 Gflops
> 
> Thanks,
> 
> ================================
>  Keita Teranishi
>  Scientific Library Group
>  Cray, Inc.
>  keita at cray.com
> ================================
> 
> 
> -----Original Message-----
> From: petsc-dev-bounces at mcs.anl.gov [mailto:petsc-dev-bounces at mcs.anl.gov] On Behalf Of Barry Smith
> Sent: Friday, August 27, 2010 2:15 PM
> To: For users of the development version of PETSc
> Subject: [petsc-dev] [GPU] Performance on Fermi
> 
> 
>   PETSc-dev folks,
> 
>      Please prepend all messages to petsc-dev that involve GPUs with [GPU] so they can be easily filtered.
> 
>    Keita,
> 
>      To run src/ksp/ksp/examples/tutorials/ex2.c with CUDA you need the flag -vec_type cuda
> 
>      Note also that this example is fine for simple ONE processor tests but should not be used for parallel testing because it does not do a proper parallel partitioning for performance
> 
>    Barry
> 
> On Aug 27, 2010, at 2:04 PM, Keita Teranishi wrote:
> 
>> Hi,
>> 
>> I ran ex2.c with a matrix from 512x512 grid. 
>> I set CG and Jacobi for the solver and preconditioner. 
>> GCC-4.4.4 and CUDA-3.1 are used to compile the code.
>> BLAS and LAPAKCK are not optimized.
>> 
>> MatMult
>> Fermi: 		1142 MFlops
>> 1 core Istanbul:	420 MFlops
>> 
>> KSPSolve:
>> Fermi:			1.5 Sec
>> 1 core Istanbul:	1.7 Sec
>> 
>> 
>> ================================
>> Keita Teranishi
>> Scientific Library Group
>> Cray, Inc.
>> keita at cray.com
>> ================================
>> 
>> 
>> -----Original Message-----
>> From: petsc-dev-bounces at mcs.anl.gov 
>> [mailto:petsc-dev-bounces at mcs.anl.gov] On Behalf Of Satish Balay
>> Sent: Friday, August 27, 2010 1:49 PM
>> To: For users of the development version of PETSc
>> Subject: Re: [petsc-dev] Problem with petsc-dev
>> 
>> On Fri, 27 Aug 2010, Satish Balay wrote:
>> 
>>> There was a problem with tarball creation for the past few days. Will 
>>> try to respin manually today - and update you.
>> 
>> the petsc-dev tarball is now updated on the website..
>> 
>> Satish
>