Hi All, Apologies in advance if this is a silly question, or a repeat.
I recently noticed that the OoO core squashes itself and all younger instructions when a load is issued to the memory system, but the cache is blocked (say the MSHRs are full, or there are no targets left). Contrarily, when a write is issued to the memory system, the store will simply retry until the cache can handle the request.
There is potentially some performance penalty in squashing these loads, and a large energy penalty as well (can be up to 2x for the core in some contrived cases, according to mcpat). Given that these squashes can occur frequently in memory-bound programs, is there a reason this was chosen as the implementation? Is there a reason why loads can't be stalled and retried on a cache block?
Thanks! Tony _______________________________________________ gem5-users mailing list gem5-users@gem5.org http://m5sim.org/cgi-bin/mailman/listinfo/gem5-users
