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Compared with baseline: >> NI_TARGET +7% >> NI_SPARE -3% >> NI_RUNNABLE -4% >> NI_RANDOM -3% >> >> So NI_TARGET reverts the performance regression. >> The other options brings more regression for SpecJBB. > > Excellent, how does NI_TARGET+NI_RANDOM work for you? Like Chris, I > found that the schbench workload was really suffering from doing too > many idle balance attempts that weren't really working out. > > NI_RANDOM reduces the number of newidle balances based on the success > ratio. Eg. if you have successful balancing 25% of the time, it will do > 1 in 4 balances and count a successful balance as 4 to keep the > accounting straight. > > So workloads with a high success rate will keep newidle balance calls > frequent, while workloads with a low success rate (like schbench) will > greatly reduce the number of calls. Please see the test result of SpecJBB critical-jOPS on AmpereOne: Baseline: v6.17+patch NI_TARGET: +6% NI_TARGET+NI_RANDOM: +5% NI_TARGET+NI_SPARE: +4% NI_TARGET+NI_RUNNABLE: +2% "NI_TARGET+NI_RANDOM" and "NI_TARGET" are very close. I will do more test. Thanks, -adam