The other tricky part is how the simple cache will mirror the simulated cache hierarchy. One way to solve both problems is to warm up only the LLC .
> Is this a silly idea? Is it worth it to try to implement or will it just be > a waste of time since the beginning behavior will be transient and won't > last very long? On Wed, Dec 7, 2011 at 10:54 AM, DRAM Ninjas <[email protected]> wrote: > Greetings all, > > I was thinking the other day that it would be very nice to have a way to > warm up caches before an ROI starts. I just wanted any input about how hard > it would be to implement. I think maybe it wouldn't be that hard: > > - First, add a ptlcall to trigger a warmup operation -- this would probably > be done at the shell via a small script like 'start_sim' before an ROI > workload is launched > - Then, instrument the qemu load/store functions to run a simple cache model > -- we probably don't have to do full coherence and all that -- just sort of > fill in tags as requests are made. This wouldn't be *that* accurate, but at > least it would approximate what the caches might have in them so that there > aren't tons of false compulsory misses at the beginning of an ROI. > - Finally, when a ptlcall_switch_to_sim is issued -- copy the tags from the > simple cache model state into the full simulation cache model and begin > simulating as usual. The real trick here would be if the simple cache model > doesn't do coherence, to figure out what the states of the cache lines > should be (exclusive, shared, owned?). > > Is this a silly idea? Is it worth it to try to implement or will it just be > a waste of time since the beginning behavior will be transient and won't > last very long? > > -Paul > > > > > > _______________________________________________ > http://www.marss86.org > Marss86-Devel mailing list > [email protected] > https://www.cs.binghamton.edu/mailman/listinfo/marss86-devel > _______________________________________________ http://www.marss86.org Marss86-Devel mailing list [email protected] https://www.cs.binghamton.edu/mailman/listinfo/marss86-devel
