aboutsummaryrefslogtreecommitdiff
path: root/benchtests
diff options
context:
space:
mode:
authorWangyang Guo <wangyang.guo@intel.com>2022-04-21 03:28:41 +0000
committerH.J. Lu <hjl.tools@gmail.com>2022-04-27 13:41:57 -0700
commit9e5daa1f6a709dd42420f10971889dc1e47b6e92 (patch)
tree0ce769cb83510afbdd62afce1a333f1b8cd0172b /benchtests
parent834ddd0432f68d6dc85b6aac95065721af0d86e9 (diff)
downloadglibc-9e5daa1f6a709dd42420f10971889dc1e47b6e92.zip
glibc-9e5daa1f6a709dd42420f10971889dc1e47b6e92.tar.gz
glibc-9e5daa1f6a709dd42420f10971889dc1e47b6e92.tar.bz2
benchtests: Add pthread-mutex-locks bench
Benchmark for testing pthread mutex locks performance with different threads and critical sections. The test configuration consists of 3 parts: 1. thread number 2. critical-section length 3. non-critical-section length Thread number starts from 1 and increased by 2x until num of CPU cores (nprocs). An additional over-saturation case (1.25 * nprocs) is also included. Critical-section is represented by a loop of shared do_filler(), length can be determined by the loop iters. Non-critical-section is similiar to the critical-section, except it's based on non-shared do_filler(). Currently, adaptive pthread_mutex lock is tested.
Diffstat (limited to 'benchtests')
-rw-r--r--benchtests/Makefile2
-rw-r--r--benchtests/bench-pthread-mutex-locks.c288
2 files changed, 290 insertions, 0 deletions
diff --git a/benchtests/Makefile b/benchtests/Makefile
index 8dfca59..b477042 100644
--- a/benchtests/Makefile
+++ b/benchtests/Makefile
@@ -102,6 +102,7 @@ endif
bench-pthread := \
pthread-locks \
+ pthread-mutex-locks \
pthread_once \
thread_create \
# bench-pthread
@@ -281,6 +282,7 @@ $(addprefix $(objpfx)bench-,$(math-benchset)): $(libm-benchtests)
$(addprefix $(objpfx)bench-,$(bench-pthread)): $(thread-library-benchtests)
$(addprefix $(objpfx)bench-,$(bench-malloc)): $(thread-library-benchtests)
$(addprefix $(objpfx)bench-,pthread-locks): $(libm-benchtests)
+$(addprefix $(objpfx)bench-,pthread-mutex-locks): $(libm-benchtests)
diff --git a/benchtests/bench-pthread-mutex-locks.c b/benchtests/bench-pthread-mutex-locks.c
new file mode 100644
index 0000000..1685b9d
--- /dev/null
+++ b/benchtests/bench-pthread-mutex-locks.c
@@ -0,0 +1,288 @@
+/* Measure mutex_lock for different threads and critical sections.
+ Copyright (C) 2022 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+#define TEST_MAIN
+#define TEST_NAME "pthread-mutex-locks"
+#define TIMEOUT (20 * 60)
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <math.h>
+#include <pthread.h>
+#include <sys/time.h>
+#include <sys/sysinfo.h>
+#include "bench-timing.h"
+#include "json-lib.h"
+
+static pthread_mutex_t lock;
+static pthread_mutexattr_t attr;
+static pthread_barrier_t barrier;
+
+#define START_ITERS 1000
+
+#pragma GCC push_options
+#pragma GCC optimize(1)
+
+static int __attribute__ ((noinline)) fibonacci (int i)
+{
+ asm("");
+ if (i > 2)
+ return fibonacci (i - 1) + fibonacci (i - 2);
+ return 10 + i;
+}
+
+static void
+do_filler (void)
+{
+ char buf1[512], buf2[512];
+ int f = fibonacci (4);
+ memcpy (buf1, buf2, f);
+}
+
+static void
+do_filler_shared (void)
+{
+ static char buf1[512], buf2[512];
+ int f = fibonacci (4);
+ memcpy (buf1, buf2, f);
+}
+
+#pragma GCC pop_options
+
+#define UNIT_WORK_CRT do_filler_shared ()
+#define UNIT_WORK_NON_CRT do_filler ()
+
+static inline void
+critical_section (int length)
+{
+ for (int i = length; i >= 0; i--)
+ UNIT_WORK_CRT;
+}
+
+static inline void
+non_critical_section (int length)
+{
+ for (int i = length; i >= 0; i--)
+ UNIT_WORK_NON_CRT;
+}
+
+typedef struct Worker_Params
+{
+ long iters;
+ int crt_len;
+ int non_crt_len;
+ timing_t duration;
+} Worker_Params;
+
+static void *
+worker (void *v)
+{
+ timing_t start, stop;
+ Worker_Params *p = (Worker_Params *) v;
+ long iters = p->iters;
+ int crt_len = p->crt_len;
+ int non_crt_len = p->non_crt_len;
+
+ pthread_barrier_wait (&barrier);
+ TIMING_NOW (start);
+ while (iters--)
+ {
+ pthread_mutex_lock (&lock);
+ critical_section (crt_len);
+ pthread_mutex_unlock (&lock);
+ non_critical_section (non_crt_len);
+ }
+ TIMING_NOW (stop);
+
+ TIMING_DIFF (p->duration, start, stop);
+ return NULL;
+}
+
+static double
+do_one_test (int num_threads, int crt_len, int non_crt_len, long iters)
+{
+ int i;
+ timing_t mean;
+ Worker_Params *p, params[num_threads];
+ pthread_t threads[num_threads];
+
+ pthread_mutex_init (&lock, &attr);
+ pthread_barrier_init (&barrier, NULL, num_threads);
+
+ for (i = 0; i < num_threads; i++)
+ {
+ p = &params[i];
+ p->iters = iters;
+ p->crt_len = crt_len;
+ p->non_crt_len = non_crt_len;
+ pthread_create (&threads[i], NULL, worker, (void *) p);
+ }
+ for (i = 0; i < num_threads; i++)
+ pthread_join (threads[i], NULL);
+
+ pthread_mutex_destroy (&lock);
+ pthread_barrier_destroy (&barrier);
+
+ mean = 0;
+ for (i = 0; i < num_threads; i++)
+ mean += params[i].duration;
+ mean /= num_threads;
+ return mean;
+}
+
+#define RUN_COUNT 10
+#define MIN_TEST_SEC 0.01
+
+static void
+do_bench_one (const char *name, int num_threads, int crt_len, int non_crt_len,
+ json_ctx_t *js)
+{
+ timing_t cur;
+ struct timeval ts, te;
+ double tsd, ted, td;
+ long iters, iters_limit, total_iters;
+ timing_t curs[RUN_COUNT + 2];
+ int i, j;
+ double mean, stdev;
+
+ iters = START_ITERS;
+ iters_limit = LONG_MAX / 100;
+
+ while (1)
+ {
+ gettimeofday (&ts, NULL);
+ cur = do_one_test (num_threads, crt_len, non_crt_len, iters);
+ gettimeofday (&te, NULL);
+ /* Make sure the test to run at least MIN_TEST_SEC. */
+ tsd = ts.tv_sec + ts.tv_usec / 1000000.0;
+ ted = te.tv_sec + te.tv_usec / 1000000.0;
+ td = ted - tsd;
+ if (td >= MIN_TEST_SEC || iters >= iters_limit)
+ break;
+
+ iters *= 10;
+ }
+
+ curs[0] = cur;
+ for (i = 1; i < RUN_COUNT + 2; i++)
+ curs[i] = do_one_test (num_threads, crt_len, non_crt_len, iters);
+
+ /* Sort the results so we can discard the fastest and slowest
+ times as outliers. */
+ for (i = 0; i < RUN_COUNT + 1; i++)
+ for (j = i + 1; j < RUN_COUNT + 2; j++)
+ if (curs[i] > curs[j])
+ {
+ timing_t temp = curs[i];
+ curs[i] = curs[j];
+ curs[j] = temp;
+ }
+
+ /* Calculate mean and standard deviation. */
+ mean = 0.0;
+ total_iters = iters * num_threads;
+ for (i = 1; i < RUN_COUNT + 1; i++)
+ mean += (double) curs[i] / (double) total_iters;
+ mean /= RUN_COUNT;
+
+ stdev = 0.0;
+ for (i = 1; i < RUN_COUNT + 1; i++)
+ {
+ double s = (double) curs[i] / (double) total_iters - mean;
+ stdev += s * s;
+ }
+ stdev = sqrt (stdev / (RUN_COUNT - 1));
+
+ char buf[256];
+ snprintf (buf, sizeof buf, "%s,non_crt_len=%d,crt_len=%d,threads=%d", name,
+ non_crt_len, crt_len, num_threads);
+
+ json_attr_object_begin (js, buf);
+
+ json_attr_double (js, "duration", (double) cur);
+ json_attr_double (js, "iterations", (double) total_iters);
+ json_attr_double (js, "mean", mean);
+ json_attr_double (js, "stdev", stdev);
+ json_attr_double (js, "min-outlier",
+ (double) curs[0] / (double) total_iters);
+ json_attr_double (js, "min", (double) curs[1] / (double) total_iters);
+ json_attr_double (js, "max",
+ (double) curs[RUN_COUNT] / (double) total_iters);
+ json_attr_double (js, "max-outlier",
+ (double) curs[RUN_COUNT + 1] / (double) total_iters);
+
+ json_attr_object_end (js);
+}
+
+#define TH_CONF_MAX 10
+
+int
+do_bench (void)
+{
+ int rv = 0;
+ json_ctx_t json_ctx;
+ int i, j, k;
+ int th_num, th_conf, nprocs;
+ int threads[TH_CONF_MAX];
+ int crt_lens[] = { 0, 1, 2, 4, 8, 16, 32, 64, 128 };
+ int non_crt_lens[] = { 1, 32, 128 };
+ char name[128];
+
+ json_init (&json_ctx, 2, stdout);
+ json_attr_object_begin (&json_ctx, "pthread_mutex_locks");
+
+ /* The thread config begins from 1, and increases by 2x until nprocs.
+ We also wants to test over-saturation case (1.25*nprocs). */
+ nprocs = get_nprocs ();
+ th_num = 1;
+ for (th_conf = 0; th_conf < (TH_CONF_MAX - 2) && th_num < nprocs; th_conf++)
+ {
+ threads[th_conf] = th_num;
+ th_num <<= 1;
+ }
+ threads[th_conf++] = nprocs;
+ threads[th_conf++] = nprocs + nprocs / 4;
+
+ pthread_mutexattr_init (&attr);
+ pthread_mutexattr_settype (&attr, PTHREAD_MUTEX_ADAPTIVE_NP);
+ snprintf (name, sizeof name, "type=adaptive");
+
+ for (k = 0; k < (sizeof (non_crt_lens) / sizeof (int)); k++)
+ {
+ int non_crt_len = non_crt_lens[k];
+ for (j = 0; j < (sizeof (crt_lens) / sizeof (int)); j++)
+ {
+ int crt_len = crt_lens[j];
+ for (i = 0; i < th_conf; i++)
+ {
+ th_num = threads[i];
+ do_bench_one (name, th_num, crt_len, non_crt_len, &json_ctx);
+ }
+ }
+ }
+
+ json_attr_object_end (&json_ctx);
+
+ return rv;
+}
+
+#define TEST_FUNCTION do_bench ()
+
+#include "../test-skeleton.c"