> On Sept. 19, 2014, 3:40 p.m., Andreas Hansson wrote: > > I'm just curious to know, do you think we will manage to eventually get the > > network power online again? It just seems unfortunate that we have to rely > > on post processing. I see how it is a step-wise modification, but perhaps > > it would be worth keeping parts of this if we will eventually go back to > > calling the power models while running. > > > > We are about to add DRAMPower to ext to achieve exactly what I describe > > above. Ultimately I think it is better if the power numbers are available > > on-line. Less traces, less scripts, the possibility to do on-line > > power-aware decisions etc. > > Brad Beckmann wrote: > Ideally that would be a great feature to have. I think the key is to > avoid a lot of internal hacking of individual objects, like the code Nilay is > removing in this patch. I'm not sure what the best final solution is. Could > we dyncamically call the python scripts during simulation? Could we somehow > directly incorporate the power model components into the sim object hierarchy? > > Nilay Vaish wrote: > I think it is straight forward to invoke python scripts during > simulation. We do it > all the time, don't we? We can have pseudo instructions in the > application that > moves us back into the python hierarchy and then invokes the script. Or > else, we can > have periodic intervals at which the simulator would return to python and > compute the > power consumption for the interval gone by. I think both these can be > realized with > some understanding how things work currently. I think we should let the > users decide > how they want to do it.
I am not opposed this patch going in as is, but there are definitely reasons to avoid the C++ -> Python -> C++ ping-ponging. #1 Performance. We have seen massive drops when using Python to do the power equation calculations. Of course it depends on granularity, but even in very realistic cases it is a massive problem. #2 Dependency on Python. We are about to push a number of patches that allows gem5 to operate entirely without Python. This is important when using it hosted in other simulation frameworks e.g. SystemC or SST. - Andreas ----------------------------------------------------------- This is an automatically generated e-mail. To reply, visit: http://reviews.gem5.org/r/2404/#review5340 ----------------------------------------------------------- On Sept. 18, 2014, 9:23 p.m., Nilay Vaish wrote: > > ----------------------------------------------------------- > This is an automatically generated e-mail. To reply, visit: > http://reviews.gem5.org/r/2404/ > ----------------------------------------------------------- > > (Updated Sept. 18, 2014, 9:23 p.m.) > > > Review request for Default. > > > Repository: gem5 > > > Description > ------- > > Changeset 10373:f72ea8945c90 > --------------------------- > ruby: network: garnet: remove functions for computing power > > > Diffs > ----- > > src/mem/ruby/network/garnet/fixed-pipeline/GarnetNetwork_d.hh 4466307b8a2a > src/mem/ruby/network/garnet/fixed-pipeline/GarnetNetwork_d.cc 4466307b8a2a > src/mem/ruby/network/garnet/fixed-pipeline/NetworkLink_d.hh 4466307b8a2a > src/mem/ruby/network/garnet/fixed-pipeline/Router_d.hh 4466307b8a2a > src/mem/ruby/network/garnet/fixed-pipeline/Router_d.cc 4466307b8a2a > > Diff: http://reviews.gem5.org/r/2404/diff/ > > > Testing > ------- > > > Thanks, > > Nilay Vaish > > _______________________________________________ gem5-dev mailing list [email protected] http://m5sim.org/mailman/listinfo/gem5-dev
