Hi, look at the FAQ http://www.mcs.anl.gov/petsc/documentation/faq.html#slowerparallel
"There must be enough work for each process to overweigh the communication time. We recommend an absolute minimum of about 10,000 unknowns per process, better is 20,000 or more." Regards Thomas Huxhorn On 08/03/2012 09:03 AM, TAY wee-beng wrote: > Hi, > > I remembered that in one of the mails, someone mentions the recommended > unknowns on each processor when doing parallel solving. > > However, I can't find that mail. Can someone enlighten me? Also, is this > number problem dependent? > > Btw, I'm using PETSc to solve linear equations using BCGS. > > Thanks! >
