From patchwork Mon Jun 20 22:25:54 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Dave Marchevsky X-Patchwork-Id: 12888336 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4688BC43334 for ; Mon, 20 Jun 2022 22:26:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236625AbiFTW0H (ORCPT ); Mon, 20 Jun 2022 18:26:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41234 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238210AbiFTW0G (ORCPT ); Mon, 20 Jun 2022 18:26:06 -0400 Received: from mx0b-00082601.pphosted.com (mx0b-00082601.pphosted.com [67.231.153.30]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B584413EB2 for ; Mon, 20 Jun 2022 15:26:01 -0700 (PDT) Received: from pps.filterd (m0148460.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 25KM21fk002899 for ; Mon, 20 Jun 2022 15:26:00 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : content-type : content-transfer-encoding : mime-version; s=facebook; bh=PAphrrDm/CoKJ2UkckC0MBt7g83Ix/YwC5Mv8R4KCAc=; b=ev7ASktLqoU6ApwgP3nzlyorEIoI8vOxRhQWR8Iw65A+myGH3bpdRg8ZEyhrbeFEtjn8 j0PbWfq1jvVX9qjP6s/qCkRT/2iSV1b9cREVAKLgxohyG9tnoCm8jNxWnoXx5ZaM2IJT G35xRDBgkmSMbxa+ekZmjLXKh3dkadP0W8o= Received: from mail.thefacebook.com ([163.114.132.120]) by mx0a-00082601.pphosted.com (PPS) with ESMTPS id 3gsc7wuxe1-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Mon, 20 Jun 2022 15:26:00 -0700 Received: from twshared10560.18.frc3.facebook.com (2620:10d:c085:208::11) by mail.thefacebook.com (2620:10d:c085:21d::4) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.28; Mon, 20 Jun 2022 15:25:58 -0700 Received: by devbig077.ldc1.facebook.com (Postfix, from userid 158236) id 4FB8993D76F6; Mon, 20 Jun 2022 15:25:55 -0700 (PDT) From: Dave Marchevsky To: CC: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Kernel Team , Dave Marchevsky Subject: [PATCH v6 bpf-next] selftests/bpf: Add benchmark for local_storage get Date: Mon, 20 Jun 2022 15:25:54 -0700 Message-ID: <20220620222554.270578-1-davemarchevsky@fb.com> X-Mailer: git-send-email 2.30.2 X-FB-Internal: Safe X-Proofpoint-GUID: PlV8IY-TqKfLoNAmtFRFeej5KfJZrSrf X-Proofpoint-ORIG-GUID: PlV8IY-TqKfLoNAmtFRFeej5KfJZrSrf X-Proofpoint-UnRewURL: 0 URL was un-rewritten MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.883,Hydra:6.0.517,FMLib:17.11.64.514 definitions=2022-06-20_05,2022-06-17_01,2022-02-23_01 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net Add a benchmarks to demonstrate the performance cliff for local_storage get as the number of local_storage maps increases beyond current local_storage implementation's cache size. "sequential get" and "interleaved get" benchmarks are added, both of which do many bpf_task_storage_get calls on sets of task local_storage maps of various counts, while considering a single specific map to be 'important' and counting task_storage_gets to the important map separately in addition to normal 'hits' count of all gets. Goal here is to mimic scenario where a particular program using one map - the important one - is running on a system where many other local_storage maps exist and are accessed often. While "sequential get" benchmark does bpf_task_storage_get for map 0, 1, ..., {9, 99, 999} in order, "interleaved" benchmark interleaves 4 bpf_task_storage_gets for the important map for every 10 map gets. This is meant to highlight performance differences when important map is accessed far more frequently than non-important maps. A "hashmap control" benchmark is also included for easy comparison of standard bpf hashmap lookup vs local_storage get. The benchmark is similar to "sequential get", but creates and uses BPF_MAP_TYPE_HASH instead of local storage. Only one inner map is created - a hashmap meant to hold tid -> data mapping for all tasks. Size of the hashmap is hardcoded to my system's PID_MAX_LIMIT (4,194,304). The number of these keys which are actually fetched as part of the benchmark is configurable. Addition of this benchmark is inspired by conversation with Alexei in a previous patchset's thread [0], which highlighted the need for such a benchmark to motivate and validate improvements to local_storage implementation. My approach in that series focused on improving performance for explicitly-marked 'important' maps and was rejected with feedback to make more generally-applicable improvements while avoiding explicitly marking maps as important. Thus the benchmark reports both general and important-map-focused metrics, so effect of future work on both is clear. Regarding the benchmark results. On a powerful system (Skylake, 20 cores, 256gb ram): Hashmap Control =============== num keys: 10 hashmap (control) sequential get: hits throughput: 20.900 ± 0.334 M ops/s, hits latency: 47.847 ns/op, important_hits throughput: 20.900 ± 0.334 M ops/s num keys: 1000 hashmap (control) sequential get: hits throughput: 13.758 ± 0.219 M ops/s, hits latency: 72.683 ns/op, important_hits throughput: 13.758 ± 0.219 M ops/s num keys: 10000 hashmap (control) sequential get: hits throughput: 6.995 ± 0.034 M ops/s, hits latency: 142.959 ns/op, important_hits throughput: 6.995 ± 0.034 M ops/s num keys: 100000 hashmap (control) sequential get: hits throughput: 4.452 ± 0.371 M ops/s, hits latency: 224.635 ns/op, important_hits throughput: 4.452 ± 0.371 M ops/s num keys: 4194304 hashmap (control) sequential get: hits throughput: 3.043 ± 0.033 M ops/s, hits latency: 328.587 ns/op, important_hits throughput: 3.043 ± 0.033 M ops/s Local Storage ============= num_maps: 1 local_storage cache sequential get: hits throughput: 47.298 ± 0.180 M ops/s, hits latency: 21.142 ns/op, important_hits throughput: 47.298 ± 0.180 M ops/s local_storage cache interleaved get: hits throughput: 55.277 ± 0.888 M ops/s, hits latency: 18.091 ns/op, important_hits throughput: 55.277 ± 0.888 M ops/s num_maps: 10 local_storage cache sequential get: hits throughput: 40.240 ± 0.802 M ops/s, hits latency: 24.851 ns/op, important_hits throughput: 4.024 ± 0.080 M ops/s local_storage cache interleaved get: hits throughput: 48.701 ± 0.722 M ops/s, hits latency: 20.533 ns/op, important_hits throughput: 17.393 ± 0.258 M ops/s num_maps: 16 local_storage cache sequential get: hits throughput: 44.515 ± 0.708 M ops/s, hits latency: 22.464 ns/op, important_hits throughput: 2.782 ± 0.044 M ops/s local_storage cache interleaved get: hits throughput: 49.553 ± 2.260 M ops/s, hits latency: 20.181 ns/op, important_hits throughput: 15.767 ± 0.719 M ops/s num_maps: 17 local_storage cache sequential get: hits throughput: 38.778 ± 0.302 M ops/s, hits latency: 25.788 ns/op, important_hits throughput: 2.284 ± 0.018 M ops/s local_storage cache interleaved get: hits throughput: 43.848 ± 1.023 M ops/s, hits latency: 22.806 ns/op, important_hits throughput: 13.349 ± 0.311 M ops/s num_maps: 24 local_storage cache sequential get: hits throughput: 19.317 ± 0.568 M ops/s, hits latency: 51.769 ns/op, important_hits throughput: 0.806 ± 0.024 M ops/s local_storage cache interleaved get: hits throughput: 24.397 ± 0.272 M ops/s, hits latency: 40.989 ns/op, important_hits throughput: 6.863 ± 0.077 M ops/s num_maps: 32 local_storage cache sequential get: hits throughput: 13.333 ± 0.135 M ops/s, hits latency: 75.000 ns/op, important_hits throughput: 0.417 ± 0.004 M ops/s local_storage cache interleaved get: hits throughput: 16.898 ± 0.383 M ops/s, hits latency: 59.178 ns/op, important_hits throughput: 4.717 ± 0.107 M ops/s num_maps: 100 local_storage cache sequential get: hits throughput: 6.360 ± 0.107 M ops/s, hits latency: 157.233 ns/op, important_hits throughput: 0.064 ± 0.001 M ops/s local_storage cache interleaved get: hits throughput: 7.303 ± 0.362 M ops/s, hits latency: 136.930 ns/op, important_hits throughput: 1.907 ± 0.094 M ops/s num_maps: 1000 local_storage cache sequential get: hits throughput: 0.452 ± 0.010 M ops/s, hits latency: 2214.022 ns/op, important_hits throughput: 0.000 ± 0.000 M ops/s local_storage cache interleaved get: hits throughput: 0.542 ± 0.007 M ops/s, hits latency: 1843.341 ns/op, important_hits throughput: 0.136 ± 0.002 M ops/s Looking at the "sequential get" results, it's clear that as the number of task local_storage maps grows beyond the current cache size (16), there's a significant reduction in hits throughput. Note that current local_storage implementation assigns a cache_idx to maps as they are created. Since "sequential get" is creating maps 0..n in order and then doing bpf_task_storage_get calls in the same order, the benchmark is effectively ensuring that a map will not be in cache when the program tries to access it. For "interleaved get" results, important-map hits throughput is greatly increased as the important map is more likely to be in cache by virtue of being accessed far more frequently. Throughput still reduces as # maps increases, though. To get a sense of the overhead of the benchmark program, I commented out bpf_task_storage_get/bpf_map_lookup_elem in local_storage_bench.c and ran the benchmark on the same host as the 'real' run. Results: Hashmap Control =============== num keys: 10 hashmap (control) sequential get: hits throughput: 54.288 ± 0.655 M ops/s, hits latency: 18.420 ns/op, important_hits throughput: 54.288 ± 0.655 M ops/s num keys: 1000 hashmap (control) sequential get: hits throughput: 52.913 ± 0.519 M ops/s, hits latency: 18.899 ns/op, important_hits throughput: 52.913 ± 0.519 M ops/s num keys: 10000 hashmap (control) sequential get: hits throughput: 53.480 ± 1.235 M ops/s, hits latency: 18.699 ns/op, important_hits throughput: 53.480 ± 1.235 M ops/s num keys: 100000 hashmap (control) sequential get: hits throughput: 54.982 ± 1.902 M ops/s, hits latency: 18.188 ns/op, important_hits throughput: 54.982 ± 1.902 M ops/s num keys: 4194304 hashmap (control) sequential get: hits throughput: 50.858 ± 0.707 M ops/s, hits latency: 19.662 ns/op, important_hits throughput: 50.858 ± 0.707 M ops/s Local Storage ============= num_maps: 1 local_storage cache sequential get: hits throughput: 110.990 ± 4.828 M ops/s, hits latency: 9.010 ns/op, important_hits throughput: 110.990 ± 4.828 M ops/s local_storage cache interleaved get: hits throughput: 161.057 ± 4.090 M ops/s, hits latency: 6.209 ns/op, important_hits throughput: 161.057 ± 4.090 M ops/s num_maps: 10 local_storage cache sequential get: hits throughput: 112.930 ± 1.079 M ops/s, hits latency: 8.855 ns/op, important_hits throughput: 11.293 ± 0.108 M ops/s local_storage cache interleaved get: hits throughput: 115.841 ± 2.088 M ops/s, hits latency: 8.633 ns/op, important_hits throughput: 41.372 ± 0.746 M ops/s num_maps: 16 local_storage cache sequential get: hits throughput: 115.653 ± 0.416 M ops/s, hits latency: 8.647 ns/op, important_hits throughput: 7.228 ± 0.026 M ops/s local_storage cache interleaved get: hits throughput: 138.717 ± 1.649 M ops/s, hits latency: 7.209 ns/op, important_hits throughput: 44.137 ± 0.525 M ops/s num_maps: 17 local_storage cache sequential get: hits throughput: 112.020 ± 1.649 M ops/s, hits latency: 8.927 ns/op, important_hits throughput: 6.598 ± 0.097 M ops/s local_storage cache interleaved get: hits throughput: 128.089 ± 1.960 M ops/s, hits latency: 7.807 ns/op, important_hits throughput: 38.995 ± 0.597 M ops/s num_maps: 24 local_storage cache sequential get: hits throughput: 92.447 ± 5.170 M ops/s, hits latency: 10.817 ns/op, important_hits throughput: 3.855 ± 0.216 M ops/s local_storage cache interleaved get: hits throughput: 128.844 ± 2.808 M ops/s, hits latency: 7.761 ns/op, important_hits throughput: 36.245 ± 0.790 M ops/s num_maps: 32 local_storage cache sequential get: hits throughput: 102.042 ± 1.462 M ops/s, hits latency: 9.800 ns/op, important_hits throughput: 3.194 ± 0.046 M ops/s local_storage cache interleaved get: hits throughput: 126.577 ± 1.818 M ops/s, hits latency: 7.900 ns/op, important_hits throughput: 35.332 ± 0.507 M ops/s num_maps: 100 local_storage cache sequential get: hits throughput: 111.327 ± 1.401 M ops/s, hits latency: 8.983 ns/op, important_hits throughput: 1.113 ± 0.014 M ops/s local_storage cache interleaved get: hits throughput: 131.327 ± 1.339 M ops/s, hits latency: 7.615 ns/op, important_hits throughput: 34.302 ± 0.350 M ops/s num_maps: 1000 local_storage cache sequential get: hits throughput: 101.978 ± 0.563 M ops/s, hits latency: 9.806 ns/op, important_hits throughput: 0.102 ± 0.001 M ops/s local_storage cache interleaved get: hits throughput: 141.084 ± 1.098 M ops/s, hits latency: 7.088 ns/op, important_hits throughput: 35.430 ± 0.276 M ops/s Adjusting for overhead, latency numbers for "hashmap control" and "sequential get" are: hashmap_control_1k: ~53.8ns hashmap_control_10k: ~124.2ns hashmap_control_100k: ~206.5ns sequential_get_1: ~12.1ns sequential_get_10: ~16.0ns sequential_get_16: ~13.8ns sequential_get_17: ~16.8ns sequential_get_24: ~40.9ns sequential_get_32: ~65.2ns sequential_get_100: ~148.2ns sequential_get_1000: ~2204ns Clearly demonstrating a cliff. In the discussion for v1 of this patch, Alexei noted that local_storage was 2.5x faster than a large hashmap when initially implemented [1]. The benchmark results show that local_storage is 5-10x faster: a long-running BPF application putting some pid-specific info into a hashmap for each pid it sees will probably see on the order of 10-100k pids. Bench numbers for hashmaps of this size are ~10x slower than sequential_get_16, but as the number of local_storage maps grows far past local_storage cache size the performance advantage shrinks and eventually reverses. When running the benchmarks it may be necessary to bump 'open files' ulimit for a successful run. [0]: https://lore.kernel.org/all/20220420002143.1096548-1-davemarchevsky@fb.com [1]: https://lore.kernel.org/bpf/20220511173305.ftldpn23m4ski3d3@MBP-98dd607d3435.dhcp.thefacebook.com/ Signed-off-by: Dave Marchevsky --- Changelog: v5 -> v6: * Prepopulate hashmap before benchmarking (Martin, Alexei) v4 -> v5: * Remove 2nd patch refactoring mean/stddev calculations (Andrii) * Change "hashmap control" benchmark to use one big hashmap w/ configurable number of keys accessed (Andrii) * Add discussion of "hashmap control" vs "sequential get" numbers v3 -> v4: * Remove ifs guarding increments in measure fn (Andrii) * Refactor to use 1 bpf prog for all 3 benchmarks w/ global vars set from userspace before load to control behavior (Andrii) * Greatly reduce variance in overhead by having benchmark bpf prog loop 10k times regardless of map count (Andrii) * Also, move sync_fetch_and_incr out of do_lookup as the guaranteed second sync_fetch_and_incr call for num_maps = 1 was adding overhead * Add second patch refactoring bench.c's mean/stddev calculations in reporting helper fns v2 -> v3: * Accessing 1k maps in ARRAY_OF_MAPS doesn't hit MAX_USED_MAPS limit, so just use 1 program (Alexei) v1 -> v2: * Adopt ARRAY_OF_MAPS approach for bpf program, allowing truly configurable # of maps (Andrii) * Add hashmap benchmark (Alexei) * Add discussion of overhead tools/testing/selftests/bpf/Makefile | 4 +- tools/testing/selftests/bpf/bench.c | 55 ++++ tools/testing/selftests/bpf/bench.h | 4 + .../bpf/benchs/bench_local_storage.c | 287 ++++++++++++++++++ .../bpf/benchs/run_bench_local_storage.sh | 24 ++ .../selftests/bpf/benchs/run_common.sh | 17 ++ .../selftests/bpf/progs/local_storage_bench.c | 104 +++++++ 7 files changed, 494 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/bpf/benchs/bench_local_storage.c create mode 100755 tools/testing/selftests/bpf/benchs/run_bench_local_storage.sh create mode 100644 tools/testing/selftests/bpf/progs/local_storage_bench.c diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile index cb8e552e1418..4fbd88a8ed9e 100644 --- a/tools/testing/selftests/bpf/Makefile +++ b/tools/testing/selftests/bpf/Makefile @@ -571,6 +571,7 @@ $(OUTPUT)/bench_bloom_filter_map.o: $(OUTPUT)/bloom_filter_bench.skel.h $(OUTPUT)/bench_bpf_loop.o: $(OUTPUT)/bpf_loop_bench.skel.h $(OUTPUT)/bench_strncmp.o: $(OUTPUT)/strncmp_bench.skel.h $(OUTPUT)/bench_bpf_hashmap_full_update.o: $(OUTPUT)/bpf_hashmap_full_update_bench.skel.h +$(OUTPUT)/bench_local_storage.o: $(OUTPUT)/local_storage_bench.skel.h $(OUTPUT)/bench.o: bench.h testing_helpers.h $(BPFOBJ) $(OUTPUT)/bench: LDLIBS += -lm $(OUTPUT)/bench: $(OUTPUT)/bench.o \ @@ -583,7 +584,8 @@ $(OUTPUT)/bench: $(OUTPUT)/bench.o \ $(OUTPUT)/bench_bloom_filter_map.o \ $(OUTPUT)/bench_bpf_loop.o \ $(OUTPUT)/bench_strncmp.o \ - $(OUTPUT)/bench_bpf_hashmap_full_update.o + $(OUTPUT)/bench_bpf_hashmap_full_update.o \ + $(OUTPUT)/bench_local_storage.o $(call msg,BINARY,,$@) $(Q)$(CC) $(CFLAGS) $(LDFLAGS) $(filter %.a %.o,$^) $(LDLIBS) -o $@ diff --git a/tools/testing/selftests/bpf/bench.c b/tools/testing/selftests/bpf/bench.c index d8aa62be996b..1e7b5d4b1f11 100644 --- a/tools/testing/selftests/bpf/bench.c +++ b/tools/testing/selftests/bpf/bench.c @@ -150,6 +150,53 @@ void ops_report_final(struct bench_res res[], int res_cnt) printf("latency %8.3lf ns/op\n", 1000.0 / hits_mean * env.producer_cnt); } +void local_storage_report_progress(int iter, struct bench_res *res, + long delta_ns) +{ + double important_hits_per_sec, hits_per_sec; + double delta_sec = delta_ns / 1000000000.0; + + hits_per_sec = res->hits / 1000000.0 / delta_sec; + important_hits_per_sec = res->important_hits / 1000000.0 / delta_sec; + + printf("Iter %3d (%7.3lfus): ", iter, (delta_ns - 1000000000) / 1000.0); + + printf("hits %8.3lfM/s ", hits_per_sec); + printf("important_hits %8.3lfM/s\n", important_hits_per_sec); +} + +void local_storage_report_final(struct bench_res res[], int res_cnt) +{ + double important_hits_mean = 0.0, important_hits_stddev = 0.0; + double hits_mean = 0.0, hits_stddev = 0.0; + int i; + + for (i = 0; i < res_cnt; i++) { + hits_mean += res[i].hits / 1000000.0 / (0.0 + res_cnt); + important_hits_mean += res[i].important_hits / 1000000.0 / (0.0 + res_cnt); + } + + if (res_cnt > 1) { + for (i = 0; i < res_cnt; i++) { + hits_stddev += (hits_mean - res[i].hits / 1000000.0) * + (hits_mean - res[i].hits / 1000000.0) / + (res_cnt - 1.0); + important_hits_stddev += + (important_hits_mean - res[i].important_hits / 1000000.0) * + (important_hits_mean - res[i].important_hits / 1000000.0) / + (res_cnt - 1.0); + } + + hits_stddev = sqrt(hits_stddev); + important_hits_stddev = sqrt(important_hits_stddev); + } + printf("Summary: hits throughput %8.3lf \u00B1 %5.3lf M ops/s, ", + hits_mean, hits_stddev); + printf("hits latency %8.3lf ns/op, ", 1000.0 / hits_mean); + printf("important_hits throughput %8.3lf \u00B1 %5.3lf M ops/s\n", + important_hits_mean, important_hits_stddev); +} + const char *argp_program_version = "benchmark"; const char *argp_program_bug_address = ""; const char argp_program_doc[] = @@ -188,12 +235,14 @@ static const struct argp_option opts[] = { extern struct argp bench_ringbufs_argp; extern struct argp bench_bloom_map_argp; extern struct argp bench_bpf_loop_argp; +extern struct argp bench_local_storage_argp; extern struct argp bench_strncmp_argp; static const struct argp_child bench_parsers[] = { { &bench_ringbufs_argp, 0, "Ring buffers benchmark", 0 }, { &bench_bloom_map_argp, 0, "Bloom filter map benchmark", 0 }, { &bench_bpf_loop_argp, 0, "bpf_loop helper benchmark", 0 }, + { &bench_local_storage_argp, 0, "local_storage benchmark", 0 }, { &bench_strncmp_argp, 0, "bpf_strncmp helper benchmark", 0 }, {}, }; @@ -397,6 +446,9 @@ extern const struct bench bench_bpf_loop; extern const struct bench bench_strncmp_no_helper; extern const struct bench bench_strncmp_helper; extern const struct bench bench_bpf_hashmap_full_update; +extern const struct bench bench_local_storage_cache_seq_get; +extern const struct bench bench_local_storage_cache_interleaved_get; +extern const struct bench bench_local_storage_cache_hashmap_control; static const struct bench *benchs[] = { &bench_count_global, @@ -432,6 +484,9 @@ static const struct bench *benchs[] = { &bench_strncmp_no_helper, &bench_strncmp_helper, &bench_bpf_hashmap_full_update, + &bench_local_storage_cache_seq_get, + &bench_local_storage_cache_interleaved_get, + &bench_local_storage_cache_hashmap_control, }; static void setup_benchmark() diff --git a/tools/testing/selftests/bpf/bench.h b/tools/testing/selftests/bpf/bench.h index fb3e213df3dc..4b15286753ba 100644 --- a/tools/testing/selftests/bpf/bench.h +++ b/tools/testing/selftests/bpf/bench.h @@ -34,6 +34,7 @@ struct bench_res { long hits; long drops; long false_hits; + long important_hits; }; struct bench { @@ -61,6 +62,9 @@ void false_hits_report_progress(int iter, struct bench_res *res, long delta_ns); void false_hits_report_final(struct bench_res res[], int res_cnt); void ops_report_progress(int iter, struct bench_res *res, long delta_ns); void ops_report_final(struct bench_res res[], int res_cnt); +void local_storage_report_progress(int iter, struct bench_res *res, + long delta_ns); +void local_storage_report_final(struct bench_res res[], int res_cnt); static inline __u64 get_time_ns(void) { diff --git a/tools/testing/selftests/bpf/benchs/bench_local_storage.c b/tools/testing/selftests/bpf/benchs/bench_local_storage.c new file mode 100644 index 000000000000..5a378c84e81f --- /dev/null +++ b/tools/testing/selftests/bpf/benchs/bench_local_storage.c @@ -0,0 +1,287 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2022 Meta Platforms, Inc. and affiliates. */ + +#include +#include + +#include "local_storage_bench.skel.h" +#include "bench.h" + +#include + +static struct { + __u32 nr_maps; + __u32 hashmap_nr_keys_used; +} args = { + .nr_maps = 1000, + .hashmap_nr_keys_used = 1000, +}; + +enum { + ARG_NR_MAPS = 6000, + ARG_HASHMAP_NR_KEYS_USED = 6001, +}; + +static const struct argp_option opts[] = { + { "nr_maps", ARG_NR_MAPS, "NR_MAPS", 0, + "Set number of local_storage maps"}, + { "hashmap_nr_keys_used", ARG_HASHMAP_NR_KEYS_USED, "NR_KEYS", + 0, "When doing hashmap test, set number of hashmap keys test uses"}, + {}, +}; + +static error_t parse_arg(int key, char *arg, struct argp_state *state) +{ + long ret; + + switch (key) { + case ARG_NR_MAPS: + ret = strtol(arg, NULL, 10); + if (ret < 1 || ret > UINT_MAX) { + fprintf(stderr, "invalid nr_maps"); + argp_usage(state); + } + args.nr_maps = ret; + break; + case ARG_HASHMAP_NR_KEYS_USED: + ret = strtol(arg, NULL, 10); + if (ret < 1 || ret > UINT_MAX) { + fprintf(stderr, "invalid hashmap_nr_keys_used"); + argp_usage(state); + } + args.hashmap_nr_keys_used = ret; + break; + default: + return ARGP_ERR_UNKNOWN; + } + + return 0; +} + +const struct argp bench_local_storage_argp = { + .options = opts, + .parser = parse_arg, +}; + +/* Keep in sync w/ array of maps in bpf */ +#define MAX_NR_MAPS 1000 +/* keep in sync w/ same define in bpf */ +#define HASHMAP_SZ 4194304 + +static void validate(void) +{ + if (env.producer_cnt != 1) { + fprintf(stderr, "benchmark doesn't support multi-producer!\n"); + exit(1); + } + if (env.consumer_cnt != 1) { + fprintf(stderr, "benchmark doesn't support multi-consumer!\n"); + exit(1); + } + + if (args.nr_maps > MAX_NR_MAPS) { + fprintf(stderr, "nr_maps must be <= 1000\n"); + exit(1); + } + + if (args.hashmap_nr_keys_used > HASHMAP_SZ) { + fprintf(stderr, "hashmap_nr_keys_used must be <= %u\n", HASHMAP_SZ); + exit(1); + } +} + +static struct { + struct local_storage_bench *skel; + void *bpf_obj; + struct bpf_map *array_of_maps; +} ctx; + +static void prepopulate_hashmap(int fd) +{ + int i, key, val; + + /* local_storage gets will have BPF_LOCAL_STORAGE_GET_F_CREATE flag set, so + * populate the hashmap for a similar comparison + */ + for (i = 0; i < HASHMAP_SZ; i++) { + key = val = i; + if (bpf_map_update_elem(fd, &key, &val, 0)) { + fprintf(stderr, "Error prepopulating hashmap (key %d)\n", key); + exit(1); + } + } +} + +static void __setup(struct bpf_program *prog, bool hashmap) +{ + struct bpf_map *inner_map; + int i, fd, mim_fd, err; + + LIBBPF_OPTS(bpf_map_create_opts, create_opts); + + if (!hashmap) + create_opts.map_flags = BPF_F_NO_PREALLOC; + + ctx.skel->rodata->num_maps = args.nr_maps; + ctx.skel->rodata->hashmap_num_keys = args.hashmap_nr_keys_used; + inner_map = bpf_map__inner_map(ctx.array_of_maps); + create_opts.btf_key_type_id = bpf_map__btf_key_type_id(inner_map); + create_opts.btf_value_type_id = bpf_map__btf_value_type_id(inner_map); + + err = local_storage_bench__load(ctx.skel); + if (err) { + fprintf(stderr, "Error loading skeleton\n"); + goto err_out; + } + + create_opts.btf_fd = bpf_object__btf_fd(ctx.skel->obj); + + mim_fd = bpf_map__fd(ctx.array_of_maps); + if (mim_fd < 0) { + fprintf(stderr, "Error getting map_in_map fd\n"); + goto err_out; + } + + for (i = 0; i < args.nr_maps; i++) { + if (hashmap) + fd = bpf_map_create(BPF_MAP_TYPE_HASH, NULL, sizeof(int), + sizeof(int), HASHMAP_SZ, &create_opts); + else + fd = bpf_map_create(BPF_MAP_TYPE_TASK_STORAGE, NULL, sizeof(int), + sizeof(int), 0, &create_opts); + if (fd < 0) { + fprintf(stderr, "Error creating map %d: %d\n", i, fd); + goto err_out; + } + + if (hashmap) + prepopulate_hashmap(fd); + + err = bpf_map_update_elem(mim_fd, &i, &fd, 0); + if (err) { + fprintf(stderr, "Error updating array-of-maps w/ map %d\n", i); + goto err_out; + } + } + + if (!bpf_program__attach(prog)) { + fprintf(stderr, "Error attaching bpf program\n"); + goto err_out; + } + + return; +err_out: + exit(1); +} + +static void hashmap_setup(void) +{ + struct local_storage_bench *skel; + + setup_libbpf(); + + skel = local_storage_bench__open(); + ctx.skel = skel; + ctx.array_of_maps = skel->maps.array_of_hash_maps; + skel->rodata->use_hashmap = 1; + skel->rodata->interleave = 0; + + __setup(skel->progs.get_local, true); +} + +static void local_storage_cache_get_setup(void) +{ + struct local_storage_bench *skel; + + setup_libbpf(); + + skel = local_storage_bench__open(); + ctx.skel = skel; + ctx.array_of_maps = skel->maps.array_of_local_storage_maps; + skel->rodata->use_hashmap = 0; + skel->rodata->interleave = 0; + + __setup(skel->progs.get_local, false); +} + +static void local_storage_cache_get_interleaved_setup(void) +{ + struct local_storage_bench *skel; + + setup_libbpf(); + + skel = local_storage_bench__open(); + ctx.skel = skel; + ctx.array_of_maps = skel->maps.array_of_local_storage_maps; + skel->rodata->use_hashmap = 0; + skel->rodata->interleave = 1; + + __setup(skel->progs.get_local, false); +} + +static void measure(struct bench_res *res) +{ + res->hits = atomic_swap(&ctx.skel->bss->hits, 0); + res->important_hits = atomic_swap(&ctx.skel->bss->important_hits, 0); +} + +static inline void trigger_bpf_program(void) +{ + syscall(__NR_getpgid); +} + +static void *consumer(void *input) +{ + return NULL; +} + +static void *producer(void *input) +{ + while (true) + trigger_bpf_program(); + + return NULL; +} + +/* cache sequential and interleaved get benchs test local_storage get + * performance, specifically they demonstrate performance cliff of + * current list-plus-cache local_storage model. + * + * cache sequential get: call bpf_task_storage_get on n maps in order + * cache interleaved get: like "sequential get", but interleave 4 calls to the + * 'important' map (idx 0 in array_of_maps) for every 10 calls. Goal + * is to mimic environment where many progs are accessing their local_storage + * maps, with 'our' prog needing to access its map more often than others + */ +const struct bench bench_local_storage_cache_seq_get = { + .name = "local-storage-cache-seq-get", + .validate = validate, + .setup = local_storage_cache_get_setup, + .producer_thread = producer, + .consumer_thread = consumer, + .measure = measure, + .report_progress = local_storage_report_progress, + .report_final = local_storage_report_final, +}; + +const struct bench bench_local_storage_cache_interleaved_get = { + .name = "local-storage-cache-int-get", + .validate = validate, + .setup = local_storage_cache_get_interleaved_setup, + .producer_thread = producer, + .consumer_thread = consumer, + .measure = measure, + .report_progress = local_storage_report_progress, + .report_final = local_storage_report_final, +}; + +const struct bench bench_local_storage_cache_hashmap_control = { + .name = "local-storage-cache-hashmap-control", + .validate = validate, + .setup = hashmap_setup, + .producer_thread = producer, + .consumer_thread = consumer, + .measure = measure, + .report_progress = local_storage_report_progress, + .report_final = local_storage_report_final, +}; diff --git a/tools/testing/selftests/bpf/benchs/run_bench_local_storage.sh b/tools/testing/selftests/bpf/benchs/run_bench_local_storage.sh new file mode 100755 index 000000000000..2eb2b513a173 --- /dev/null +++ b/tools/testing/selftests/bpf/benchs/run_bench_local_storage.sh @@ -0,0 +1,24 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 + +source ./benchs/run_common.sh + +set -eufo pipefail + +header "Hashmap Control" +for i in 10 1000 10000 100000 4194304; do +subtitle "num keys: $i" + summarize_local_storage "hashmap (control) sequential get: "\ + "$(./bench --nr_maps 1 --hashmap_nr_keys_used=$i local-storage-cache-hashmap-control)" + printf "\n" +done + +header "Local Storage" +for i in 1 10 16 17 24 32 100 1000; do +subtitle "num_maps: $i" + summarize_local_storage "local_storage cache sequential get: "\ + "$(./bench --nr_maps $i local-storage-cache-seq-get)" + summarize_local_storage "local_storage cache interleaved get: "\ + "$(./bench --nr_maps $i local-storage-cache-int-get)" + printf "\n" +done diff --git a/tools/testing/selftests/bpf/benchs/run_common.sh b/tools/testing/selftests/bpf/benchs/run_common.sh index 6c5e6023a69f..d9f40af82006 100644 --- a/tools/testing/selftests/bpf/benchs/run_common.sh +++ b/tools/testing/selftests/bpf/benchs/run_common.sh @@ -41,6 +41,16 @@ function ops() echo "$*" | sed -E "s/.*latency\s+([0-9]+\.[0-9]+\sns\/op).*/\1/" } +function local_storage() +{ + echo -n "hits throughput: " + echo -n "$*" | sed -E "s/.* hits throughput\s+([0-9]+\.[0-9]+ ± [0-9]+\.[0-9]+\sM\sops\/s).*/\1/" + echo -n -e ", hits latency: " + echo -n "$*" | sed -E "s/.* hits latency\s+([0-9]+\.[0-9]+\sns\/op).*/\1/" + echo -n ", important_hits throughput: " + echo "$*" | sed -E "s/.*important_hits throughput\s+([0-9]+\.[0-9]+ ± [0-9]+\.[0-9]+\sM\sops\/s).*/\1/" +} + function total() { echo "$*" | sed -E "s/.*total operations\s+([0-9]+\.[0-9]+ ± [0-9]+\.[0-9]+M\/s).*/\1/" @@ -67,6 +77,13 @@ function summarize_ops() printf "%-20s %s\n" "$bench" "$(ops $summary)" } +function summarize_local_storage() +{ + bench="$1" + summary=$(echo $2 | tail -n1) + printf "%-20s %s\n" "$bench" "$(local_storage $summary)" +} + function summarize_total() { bench="$1" diff --git a/tools/testing/selftests/bpf/progs/local_storage_bench.c b/tools/testing/selftests/bpf/progs/local_storage_bench.c new file mode 100644 index 000000000000..2c3234c5b73a --- /dev/null +++ b/tools/testing/selftests/bpf/progs/local_storage_bench.c @@ -0,0 +1,104 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2022 Meta Platforms, Inc. and affiliates. */ + +#include "vmlinux.h" +#include +#include "bpf_misc.h" + +#define HASHMAP_SZ 4194304 + +struct { + __uint(type, BPF_MAP_TYPE_ARRAY_OF_MAPS); + __uint(max_entries, 1000); + __type(key, int); + __type(value, int); + __array(values, struct { + __uint(type, BPF_MAP_TYPE_TASK_STORAGE); + __uint(map_flags, BPF_F_NO_PREALLOC); + __type(key, int); + __type(value, int); + }); +} array_of_local_storage_maps SEC(".maps"); + +struct { + __uint(type, BPF_MAP_TYPE_ARRAY_OF_MAPS); + __uint(max_entries, 1000); + __type(key, int); + __type(value, int); + __array(values, struct { + __uint(type, BPF_MAP_TYPE_HASH); + __uint(max_entries, HASHMAP_SZ); + __type(key, int); + __type(value, int); + }); +} array_of_hash_maps SEC(".maps"); + +long important_hits; +long hits; + +/* set from user-space */ +const volatile unsigned int use_hashmap; +const volatile unsigned int hashmap_num_keys; +const volatile unsigned int num_maps; +const volatile unsigned int interleave; + +struct loop_ctx { + struct task_struct *task; + long loop_hits; + long loop_important_hits; +}; + +static int do_lookup(unsigned int elem, struct loop_ctx *lctx) +{ + void *map, *inner_map; + int idx = 0; + + if (use_hashmap) + map = &array_of_hash_maps; + else + map = &array_of_local_storage_maps; + + inner_map = bpf_map_lookup_elem(map, &elem); + if (!inner_map) + return -1; + + if (use_hashmap) { + idx = bpf_get_prandom_u32() % hashmap_num_keys; + bpf_map_lookup_elem(inner_map, &idx); + } else { + bpf_task_storage_get(inner_map, lctx->task, &idx, + BPF_LOCAL_STORAGE_GET_F_CREATE); + } + + lctx->loop_hits++; + if (!elem) + lctx->loop_important_hits++; + return 0; +} + +static long loop(u32 index, void *ctx) +{ + struct loop_ctx *lctx = (struct loop_ctx *)ctx; + unsigned int map_idx = index % num_maps; + + do_lookup(map_idx, lctx); + if (interleave && map_idx % 3 == 0) + do_lookup(0, lctx); + return 0; +} + +SEC("fentry/" SYS_PREFIX "sys_getpgid") +int get_local(void *ctx) +{ + struct loop_ctx lctx; + + lctx.task = bpf_get_current_task_btf(); + lctx.loop_hits = 0; + lctx.loop_important_hits = 0; + bpf_loop(10000, &loop, &lctx, 0); + __sync_add_and_fetch(&hits, lctx.loop_hits); + __sync_add_and_fetch(&important_hits, lctx.loop_important_hits); + return 0; +} + +char _license[] SEC("license") = "GPL";