> -----Original Message----- > From: Karl Rupp [mailto:r...@iue.tuwien.ac.at] > Sent: 10 August 2015 11:54 > To: Leoni, Massimiliano > Cc: slepc-ma...@upv.es; petsc-dev@mcs.anl.gov > Subject: Re: [petsc-dev] [GPU - slepc] Hands-on exercise 4 (SVD) not working > with GPU and default configurations
> The use of aijcusp instead of a dense matrix type certainly adds to the issue. I know, but I couldn't find a dense gpu type in the petsc manual, please correct me if there is any. > Please send the output of -log_summary so that we can see where most > time is spent. I am unable to do that as somehow I am having no output when I use that option. I also tried to explicitly call PetscLogView but still nothing is printed out. If I try with one of the slepc examples, I get the output. Why is this happening? If I run my code with -info or -log_trace I see their output, only -log_summary is shy! > If you have good (recent) CPUs in dual-socket configuration, it's more than > unlikely that you will gain anything beyond ~2x with an optimized GPU setup. > Even that ~2x may only be possible with heavily tweaking the current SVD- > implementation in SLEPc, of which I don't know the details. I used Xeon processors from 2010, just like the GPUs. This is not good news, as my supervisor is really optimist about using GPUs and getting high speed-ups! Anyway, at the moment my gpu version is several times slower than the cpu version, so even a 2x would be a win now :D Massimiliano The data contained in, or attached to, this e-mail, may contain confidential information. If you have received it in error you should notify the sender immediately by reply e-mail, delete the message from your system and contact +44 (0) 1332 622800(Security Operations Centre) if you need assistance. Please do not copy it for any purpose, or disclose its contents to any other person. An e-mail response to this address may be subject to interception or monitoring for operational reasons or for lawful business practices. (c) 2015 Rolls-Royce plc Registered office: 62 Buckingham Gate, London SW1E 6AT Company number: 1003142. Registered in England.
