Messages in this thread | | | Date | Fri, 30 Jun 2023 17:35:00 +0800 | From | Aaron Lu <> | Subject | Re: [PATCH v2] sched/task_group: Re-layout structure to reduce false sharing |
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On Wed, Jun 28, 2023 at 01:18:34PM +0800, Aaron Lu wrote: > On Tue, Jun 27, 2023 at 12:14:37PM +0200, Peter Zijlstra wrote: > > and can we still measure an improvement over this with that approach? > > Let me re-run those tests and see how things change. > > In my previous tests I didn't turn on CONFIG_RT_GROUP_SCHED. To test > this, I suppose I'll turn CONFIG_RT_GROUP_SCHED on and apply this change > here that made tg->load_avg in a dedicated cacheline, then see how > performances change with the "Make tg->load_avg per node" patch. Will > report back once done.
The test summary is: - On 2sockets/112cores/224threads SPR, it's still overall a win. Transactions of postgres_sysbench improved 47.7%, hackbench improved 13.5% and netperf improved 39.5%; - On 2sockets/64cores/128threads Icelake, hackbench and netperf have improvement while postgres_sysbench transaction slightly dropped. hackbench improved 6.2%, netperf improved 20.3% and transactions of postgres_sysbench dropped 1.2%; - On 2sockets/48cores/96threads CascadeLake, hackbench and netperf are roughly flat.
Below are detailed results:
SPR: 2socket/112cores/224threads
postgres_sysbench/1instance/100%(nr_client=nr_cpu) kernel transactions(higher is better) aligned 89623.85±0.35% per_node 132401.37±0.83%
hackbench/pipe/threads kernel time(less is better) aligned 47.43±0.48% per_node 41.02±0.69%
netperf/UDP_RR/100%(nr_client=nr_cpu) kernel throughput(higher is better) aligned 9415.97±3.81% per_node 13131.24±2.67%
ICL: 2sockets/64cores/128threads
postgres_sysbench/1instance/75% kernel transactions aligned 62291.58±0.64% per_node 61561.40±0.39%
hackbench/pipe/threads kernel time aligned 41.66±0.04% per_node 39.07±0.36%
netperf/UDP_RR/100% kernel throughput aligned 21365.01±3.32% per_node 25692.05±2.03%
CSL: 2sockets/48cores/96threads
hackbench/pipe/threads kernel time aligned: 48.78±0.61% per_node: 48.95±1.06
netperf/UDP_RR/100% kernel throughput aligned 25853.82±11.46% per_node 25264.38±0.85%
I think I'll spin a new version for the "Make tg->load_avg per-node" patch with all the information I collected.
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