On 02/05/2013 10:58 PM, Ingo Molnar wrote: > > * Alex Shi <alex....@intel.com> wrote: > >> Commit 5a50508 change to rwsem from mutex, that cause aim7 fork_test >> dropped 50%. Yuanhan liu does a good analysis, find it caused by >> strict sequential writing. Ingo suggest stealing sem writing from >> front task in waiting queue. https://lkml.org/lkml/2013/1/29/84 >> So has this patch. >> >> In this patch, I just allow writing steal happen when the >> first waiter is also writer. Then the performance fully >> recovered. > > All the aim7 fork_test performance regression is recovered?
Sure. 100% recovered on my NHM EP, NHM EX, SNB EP 2S and 4S machines. > > Thanks, > > Ingo > -- Thanks Alex -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
