From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751699AbeFDR6n (ORCPT ); Mon, 4 Jun 2018 13:58:43 -0400 Received: from mx2.suse.de ([195.135.220.15]:52808 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751217AbeFDR6j (ORCPT ); Mon, 4 Jun 2018 13:58:39 -0400 Date: Mon, 4 Jun 2018 20:01:56 +0200 From: Giovanni Gherdovich To: Srinivas Pandruvada Cc: lenb@kernel.org, rjw@rjwysocki.net, peterz@infradead.org, mgorman@techsingularity.net, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, juri.lelli@redhat.com, viresh.kumar@linaro.org Subject: Re: [RFC/RFT] [PATCH v3 0/4] Intel_pstate: HWP Dynamic performance boost Message-ID: <20180604180156.4uvb6t4xqxmuwayq@linux-h043> References: <20180531225143.34270-1-srinivas.pandruvada@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180531225143.34270-1-srinivas.pandruvada@linux.intel.com> User-Agent: NeoMutt/20170421 (1.8.2) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, May 31, 2018 at 03:51:39PM -0700, Srinivas Pandruvada wrote: > v3 > - Removed atomic bit operation as suggested. > - Added description of contention with user space. > - Removed hwp cache, boost utililty function patch and merged with util callback > patch. This way any value set is used somewhere. > > Waiting for test results from Mel Gorman, who is the original reporter. > [SNIP] Tested-by: Giovanni Gherdovich This series has an overall positive performance impact on IO both on xfs and ext4, and I'd be vary happy if it lands in v4.18. You dropped the migration optimization from v1 to v2 after the reviewers' suggestion; I'm looking forward to test that part too, so please add me to CC when you'll resend it. I've tested your series on a single socket Xeon E3-1240 v5 (Skylake, 4 cores / 8 threads) with SSD storage. The platform is a Dell PowerEdge R230. The benchmarks used are a mix of I/O intensive workloads on ext4 and xfs (dbench4, sqlite, pgbench in read/write and read-only configuration, Flexible IO aka FIO, etc) and scheduler stressers just to check that everything is okay in that department too (hackbench, pipetest, schbench, sockperf on localhost both in "throughput" and "under-load" mode, netperf in localhost, etc). There is also some HPC with the NAS Parallel Benchmark, as when using openMPI as IPC mechanism it ends up being write-intensive and that could be a good experiment, even if the HPC people aren't exactly the target audience for a frequency governor. The large improvements are in areas you already highlighted in your cover letter (dbench4, sqlite, and pgbench read/write too, very impressive honestly). Minor wins are also observed in sockperf and running the git unit tests (gitsource below). The scheduler stressers ends up, as expected, in the "neutral" category where you'll also find FIO (which given other results I'd have expected to improve a little at least). Marked "neutral" are also those results where statistical significance wasn't reached (2 standard deviations, which is roughly like a 0.05 p-value) even if they showed some difference in a direction or the other. In the "small losses" section I found hackbench run with processes (not threads) and pipes (not sockets) which I report for due diligence but looking at the raw numbers it's more of a mixed bag than a real loss, and the NAS high-perf computing benchmark when it uses openMP (as opposed to openMPI) for IPC -- but again, we often find that supercomputers people run the machines at full speed all the time. At the bottom of this message you'll find some directions if you want to run some test yourself using the same framework I used, MMTests from https://github.com/gormanm/mmtests (we store a fair amount of benchmarks parametrization up there). Large wins: - dbench4: +20% on ext4, +14% on xfs (always asynch IO) - sqlite (insert): +9% on both ext4 and xfs - pgbench (read/write): +9% on ext4, +10% on xfs Moderate wins: - sockperf (type: under-load, localhost): +1% with TCP, +5% with UDP - gisource (git unit tests, shell intensive): +3% on ext4 - NAS Parallel Benchmark (HPC, using openMPI, on xfs): +1% - tbench4 (network part of dbench4, localhost): +1% Neutral: - pgbench (read-only) on ext4 and xfs - siege - netperf (streaming and round-robin) with TCP and UDP - hackbench (sockets/process, sockets/thread and pipes/thread) - pipetest - Linux kernel build - schbench - sockperf (type: throughput) with TCP and UDP - git unit tests on xfs - FIO (both random and seq. read, both random and seq. write) on ext4 and xfs, async IO Moderate losses: - hackbench (pipes/process): -10% - NAS Parallel Benchmark with openMP: -1% Each benchmark is run with a variety of configuration parameters (eg: number of threads, number of clients, etc); to reach a final "score" the geometric mean is used (with a few exceptions depending on the type of benchmark). Detailed results follow. Amean, Hmean and Gmean are respectively arithmetic, harmonic and geometric means. For brevity I won't report all tables but only those for "large wins" and "moderate losses". Note that I'm not overly worried for the hackbench-pipes situation, as we've studied it in the past and determined that such configuration is particularly weak, time is mostly spent on contention and the scheduler code path isn't exercised. See the comment in the file configs/config-global-dhp__scheduler-unbound in MMTests for a brief description of the issue. DBENCH4 ======= NOTES: asyncronous IO; varies the number of clients up to NUMCPUS*8. MMTESTS CONFIG: global-dhp__io-dbench4-async-{ext4, xfs} MEASURES: latency (millisecs) LOWER is better EXT4 4.16.0 4.16.0 vanilla hwp-boost Amean 1 28.49 ( 0.00%) 19.68 ( 30.92%) Amean 2 26.70 ( 0.00%) 25.59 ( 4.14%) Amean 4 54.59 ( 0.00%) 43.56 ( 20.20%) Amean 8 91.19 ( 0.00%) 77.56 ( 14.96%) Amean 64 538.09 ( 0.00%) 438.67 ( 18.48%) Stddev 1 6.70 ( 0.00%) 3.24 ( 51.66%) Stddev 2 4.35 ( 0.00%) 3.57 ( 17.85%) Stddev 4 7.99 ( 0.00%) 7.24 ( 9.29%) Stddev 8 17.51 ( 0.00%) 15.80 ( 9.78%) Stddev 64 49.54 ( 0.00%) 46.98 ( 5.17%) XFS 4.16.0 4.16.0 vanilla hwp-boost Amean 1 21.88 ( 0.00%) 16.03 ( 26.75%) Amean 2 19.72 ( 0.00%) 19.82 ( -0.50%) Amean 4 37.55 ( 0.00%) 29.52 ( 21.38%) Amean 8 56.73 ( 0.00%) 51.83 ( 8.63%) Amean 64 808.80 ( 0.00%) 698.12 ( 13.68%) Stddev 1 6.29 ( 0.00%) 2.33 ( 62.99%) Stddev 2 3.12 ( 0.00%) 2.26 ( 27.73%) Stddev 4 7.56 ( 0.00%) 5.88 ( 22.28%) Stddev 8 14.15 ( 0.00%) 12.49 ( 11.71%) Stddev 64 380.54 ( 0.00%) 367.88 ( 3.33%) SQLITE ====== NOTES: SQL insert test on a table that will be 2M in size. MMTESTS CONFIG: global-dhp__db-sqlite-insert-medium-{ext4, xfs} MEASURES: transactions per second HIGHER is better EXT4 4.16.0 4.16.0 vanilla hwp-boost Hmean Trans 2098.79 ( 0.00%) 2292.16 ( 9.21%) Stddev Trans 78.79 ( 0.00%) 95.73 ( -21.50%) XFS 4.16.0 4.16.0 vanilla hwp-boost Hmean Trans 1890.27 ( 0.00%) 2058.62 ( 8.91%) Stddev Trans 52.54 ( 0.00%) 29.56 ( 43.73%) PGBENCH-RW ========== NOTES: packaged with Postgres. Varies the number of thread up to NUMCPUS. The workload is scaled so that the approximate size is 80% of of the database shared buffer which itself is 20% of RAM. The page cache is not flushed after the database is populated for the test and starts cache-hot. MMTESTS CONFIG: global-dhp__db-pgbench-timed-rw-small-{ext4, xfs} MEASURES: transactions per second HIGHER is better EXT4 4.16.0 4.16.0 vanilla hwp-boost Hmean 1 2692.19 ( 0.00%) 2660.98 ( -1.16%) Hmean 4 5218.93 ( 0.00%) 5610.10 ( 7.50%) Hmean 7 7332.68 ( 0.00%) 8378.24 ( 14.26%) Hmean 8 7462.03 ( 0.00%) 8713.36 ( 16.77%) Stddev 1 231.85 ( 0.00%) 257.49 ( -11.06%) Stddev 4 681.11 ( 0.00%) 312.64 ( 54.10%) Stddev 7 1072.07 ( 0.00%) 730.29 ( 31.88%) Stddev 8 1472.77 ( 0.00%) 1057.34 ( 28.21%) XFS 4.16.0 4.16.0 vanilla hwp-boost Hmean 1 2675.02 ( 0.00%) 2661.69 ( -0.50%) Hmean 4 5049.45 ( 0.00%) 5601.45 ( 10.93%) Hmean 7 7302.18 ( 0.00%) 8348.16 ( 14.32%) Hmean 8 7596.83 ( 0.00%) 8693.29 ( 14.43%) Stddev 1 225.41 ( 0.00%) 246.74 ( -9.46%) Stddev 4 761.33 ( 0.00%) 334.77 ( 56.03%) Stddev 7 1093.93 ( 0.00%) 811.30 ( 25.84%) Stddev 8 1465.06 ( 0.00%) 1118.81 ( 23.63%) HACKBENCH ========= NOTES: Varies the number of groups between 1 and NUMCPUS*4 MMTESTS CONFIG: global-dhp__scheduler-unbound MEASURES: time (seconds) LOWER is better 4.16.0 4.16.0 vanilla hwp-boost Amean 1 0.8350 ( 0.00%) 1.1577 ( -38.64%) Amean 3 2.8367 ( 0.00%) 3.7457 ( -32.04%) Amean 5 6.7503 ( 0.00%) 5.7977 ( 14.11%) Amean 7 7.8290 ( 0.00%) 8.0343 ( -2.62%) Amean 12 11.0560 ( 0.00%) 11.9673 ( -8.24%) Amean 18 15.2603 ( 0.00%) 15.5247 ( -1.73%) Amean 24 17.0283 ( 0.00%) 17.9047 ( -5.15%) Amean 30 19.9193 ( 0.00%) 23.4670 ( -17.81%) Amean 32 21.4637 ( 0.00%) 23.4097 ( -9.07%) Stddev 1 0.0636 ( 0.00%) 0.0255 ( 59.93%) Stddev 3 0.1188 ( 0.00%) 0.0235 ( 80.22%) Stddev 5 0.0755 ( 0.00%) 0.1398 ( -85.13%) Stddev 7 0.2778 ( 0.00%) 0.1634 ( 41.17%) Stddev 12 0.5785 ( 0.00%) 0.1030 ( 82.19%) Stddev 18 1.2099 ( 0.00%) 0.7986 ( 33.99%) Stddev 24 0.2057 ( 0.00%) 0.7030 (-241.72%) Stddev 30 1.1303 ( 0.00%) 0.7654 ( 32.28%) Stddev 32 0.2032 ( 0.00%) 3.1626 (-1456.69%) NAS PARALLEL BENCHMARK, C-CLASS (w/ openMP) =========================================== NOTES: The various computational kernels are run separately; see https://www.nas.nasa.gov/publications/npb.html for the list of tasks (IS = Integer Sort, EP = Embarrassingly Parallel, etc) MMTESTS CONFIG: global-dhp__nas-c-class-omp-full MEASURES: time (seconds) LOWER is better 4.16.0 4.16.0 vanilla hwp-boost Amean bt.C 169.82 ( 0.00%) 170.54 ( -0.42%) Stddev bt.C 1.07 ( 0.00%) 0.97 ( 9.34%) Amean cg.C 41.81 ( 0.00%) 42.08 ( -0.65%) Stddev cg.C 0.06 ( 0.00%) 0.03 ( 48.24%) Amean ep.C 26.63 ( 0.00%) 26.47 ( 0.61%) Stddev ep.C 0.37 ( 0.00%) 0.24 ( 35.35%) Amean ft.C 38.17 ( 0.00%) 38.41 ( -0.64%) Stddev ft.C 0.33 ( 0.00%) 0.32 ( 3.78%) Amean is.C 1.49 ( 0.00%) 1.40 ( 6.02%) Stddev is.C 0.20 ( 0.00%) 0.16 ( 19.40%) Amean lu.C 217.46 ( 0.00%) 220.21 ( -1.26%) Stddev lu.C 0.23 ( 0.00%) 0.22 ( 0.74%) Amean mg.C 18.56 ( 0.00%) 18.80 ( -1.31%) Stddev mg.C 0.01 ( 0.00%) 0.01 ( 22.54%) Amean sp.C 293.25 ( 0.00%) 296.73 ( -1.19%) Stddev sp.C 0.10 ( 0.00%) 0.06 ( 42.67%) Amean ua.C 170.74 ( 0.00%) 172.02 ( -0.75%) Stddev ua.C 0.28 ( 0.00%) 0.31 ( -12.89%) HOW TO REPRODUCE ================ To install MMTests, clone the git repo at https://github.com/gormanm/mmtests.git To run a config (ie a set of benchmarks, such as config-global-dhp__nas-c-class-omp-full), use the command ./run-mmtests.sh --config configs/$CONFIG $MNEMONIC-NAME from the top-level directory; the benchmark source will be downloaded from its canonical internet location, compiled and run. To compare results from two runs, use ./bin/compare-mmtests.pl --directory ./work/log \ --benchmark $BENCHMARK-NAME \ --names $MNEMONIC-NAME-1,$MNEMONIC-NAME-2 from the top-level directory. Thanks, Giovanni Gherdovich SUSE Labs