From beb52f502f0477465313675d2a0fbf3962e130b8 Mon Sep 17 00:00:00 2001 From: Wilco Dijkstra Date: Tue, 20 Jun 2017 16:26:26 +0100 Subject: Improve math benchmark infrastructure Improve support for math function benchmarking. This patch adds a feature that allows accurate benchmarking of traces extracted from real workloads. This is done by iterating over all samples rather than repeating each sample many times (which completely ignores branch prediction and cache effects). A trace can be added to existing math function inputs via "## name: workload-", followed by the trace. * benchtests/README: Describe workload feature. * benchtests/bench-skeleton.c (main): Add support for benchmarking traces from workloads. --- ChangeLog | 6 +++++ benchtests/README | 6 +++++ benchtests/bench-skeleton.c | 57 +++++++++++++++++++++++++++++++-------------- 3 files changed, 51 insertions(+), 18 deletions(-) diff --git a/ChangeLog b/ChangeLog index 2d81375..80bb1f8 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,9 @@ +2017-06-20 Wilco Dijkstra + + * benchtests/README: Describe workload feature. + * benchtests/bench-skeleton.c (main): Add support for + benchmarking traces from workloads. + 2017-06-20 Zack Weinberg * string/string.h (__mempcpy_inline): Delete. diff --git a/benchtests/README b/benchtests/README index 2c5f381..b015acf 100644 --- a/benchtests/README +++ b/benchtests/README @@ -102,6 +102,12 @@ the same file by using the `name' directive that looks something like this: See the pow-inputs file for an example of what such a partitioned input file would look like. +It is also possible to measure throughput of a (partial) trace extracted from +a real workload. In this case the whole trace is iterated over multiple times +rather than repeating every input multiple times. This can be done via: + + ##name: workload- + Benchmark Sets: ============== diff --git a/benchtests/bench-skeleton.c b/benchtests/bench-skeleton.c index 09eb78d..3c6dad7 100644 --- a/benchtests/bench-skeleton.c +++ b/benchtests/bench-skeleton.c @@ -68,34 +68,50 @@ main (int argc, char **argv) clock_gettime (CLOCK_MONOTONIC_RAW, &runtime); runtime.tv_sec += DURATION; + bool is_bench = strncmp (VARIANT (v), "workload-", 9) == 0; double d_total_i = 0; timing_t total = 0, max = 0, min = 0x7fffffffffffffff; int64_t c = 0; + uint64_t cur; while (1) { - for (i = 0; i < NUM_SAMPLES (v); i++) + if (is_bench) { - uint64_t cur; + /* Benchmark a real trace of calls - all samples are iterated + over once before repeating. This models actual use more + accurately than repeating the same sample many times. */ TIMING_NOW (start); for (k = 0; k < iters; k++) - BENCH_FUNC (v, i); + for (i = 0; i < NUM_SAMPLES (v); i++) + BENCH_FUNC (v, i); TIMING_NOW (end); - TIMING_DIFF (cur, start, end); + TIMING_ACCUM (total, cur); + d_total_i += iters * NUM_SAMPLES (v); + } + else + for (i = 0; i < NUM_SAMPLES (v); i++) + { + TIMING_NOW (start); + for (k = 0; k < iters; k++) + BENCH_FUNC (v, i); + TIMING_NOW (end); - if (cur > max) - max = cur; + TIMING_DIFF (cur, start, end); - if (cur < min) - min = cur; + if (cur > max) + max = cur; - TIMING_ACCUM (total, cur); - /* Accumulate timings for the value. In the end we will divide - by the total iterations. */ - RESULT_ACCUM (cur, v, i, c * iters, (c + 1) * iters); + if (cur < min) + min = cur; - d_total_i += iters; - } + TIMING_ACCUM (total, cur); + /* Accumulate timings for the value. In the end we will divide + by the total iterations. */ + RESULT_ACCUM (cur, v, i, c * iters, (c + 1) * iters); + + d_total_i += iters; + } c++; struct timespec curtime; @@ -117,11 +133,16 @@ main (int argc, char **argv) json_attr_double (&json_ctx, "duration", d_total_s); json_attr_double (&json_ctx, "iterations", d_total_i); - json_attr_double (&json_ctx, "max", max / d_iters); - json_attr_double (&json_ctx, "min", min / d_iters); - json_attr_double (&json_ctx, "mean", d_total_s / d_total_i); + if (is_bench) + json_attr_double (&json_ctx, "throughput", d_total_s / d_total_i); + else + { + json_attr_double (&json_ctx, "max", max / d_iters); + json_attr_double (&json_ctx, "min", min / d_iters); + json_attr_double (&json_ctx, "mean", d_total_s / d_total_i); + } - if (detailed) + if (detailed && !is_bench) { json_array_begin (&json_ctx, "timings"); -- cgit v1.1