http://ark.intel.com/products/77780/Intel-Core-i7-4930K-Processor-12M-Cache-up-to-3_90-GHz
Looks like this CPU has 4 memory channels and supports DDR3-1866 memory. So to get max memory bandwidth - you should make sure you have: - DDR3-1866 [or PC3-14900] memory installed. - have 4 memory cards [or multiple of 4] installed. Satish On Thu, 23 Apr 2015, siddhesh godbole wrote: > Matt > > So that means the time on 10 processes in merely 1.8 times the time on 1 > process?? this is quite difficult to digest! Okay so if memory bandwidth > a controlling factor here how will forming a cluster with same machines > solve this problem? > my cpu has max memory bandwidth of 59 GB/s . > > > Apologies if the question are too silly! > > *Siddhesh M Godbole* > > 5th year Dual Degree, > Civil Eng & Applied Mech. > IIT Madras > > On Thu, Apr 23, 2015 at 4:22 PM, Matthew Knepley <[email protected]> wrote: > > > On Thu, Apr 23, 2015 at 5:47 AM, siddhesh godbole < > > [email protected]> wrote: > > > >> Hello, > >> > >> I want to know about the test which is conducted just after the PETSC is > >> configured on the system to assess the possible speedup by MPI processes. I > >> have saved the result file which says: > >> *Number of MPI processes 10* > >> *Process 0 iitm* > >> *Process 1 iitm* > >> *Process 2 iitm* > >> *Process 3 iitm* > >> *Process 4 iitm* > >> *Process 5 iitm* > >> *Process 6 iitm* > >> *Process 7 iitm* > >> *Process 8 iitm* > >> *Process 9 iitm* > >> *Function Rate (MB/s) * > >> *Copy: 24186.8271* > >> *Scale: 23914.0401* > >> *Add: 27271.7149* > >> *Triad: 27787.1630* > >> *------------------------------------------------* > >> *np speedup* > >> *1 1.0* > >> *2 1.75* > >> *3 1.86* > >> *4 1.84* > >> *5 1.85* > >> *6 1.83* > >> *7 1.76* > >> *8 1.79* > >> *9 1.8* > >> *10 1.8* > >> *Estimation of possible speedup of MPI programs based on Streams > >> benchmark.* > >> > >> 1) What parameters the speedup depends on? > >> > > > > I am not sure what you are asking here. Speedup is defined as the time T > > on 1 process divided > > by the time T_p on p processes: > > > > S = T/T_p > > > > > >> 2) what are the hardware requirements for higher speedup? ( i was > >> expecting atleast 5 times speedup after generating 10 processes. > >> > > > > STREAMS measures the speedup of vectors operations, which are very similar > > to sparse matrix operations. Both > > are limited by memory bandwidth. > > > > > >> 3) what could possibly be done to improve this ? > >> > > > > 1) You could buy more nodes, since each node has a path to memory > > > > 2) You could change algorithms, but this has proven very difficult > > > > Thanks, > > > > Matt > > > > > >> i have intel® Core™ i7-4930K CPU @ 3.40GHz × 12 with 32 GB of RAM and 1 > >> TB disk space. > >> > >> > >> Thanks > >> *Siddhesh M Godbole* > >> > >> 5th year Dual Degree, > >> Civil Eng & Applied Mech. > >> IIT Madras > >> > > > > > > > > -- > > What most experimenters take for granted before they begin their > > experiments is infinitely more interesting than any results to which their > > experiments lead. > > -- Norbert Wiener > > >
