Add a microbench mark which test the performance of taking and
releasing a read lease with many processes in a tight loop.
Based on posix02.
Signed-off-by: Daniel Wagner <daniel.wagner@xxxxxxxxxxxx>
---
Makefile.am | 2 +-
lease02.c | 178 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 179 insertions(+), 1 deletion(-)
create mode 100644 lease02.c
diff --git a/Makefile.am b/Makefile.am
index b0a2851..4a2ae98 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -4,6 +4,6 @@ ACLOCAL_AMFLAGS = -I m4
EXTRA_DIST = m4/gnulib-cache.m4
LDADD = lib/libgnu.a -lrt
-bin_PROGRAMS = flock01 flock02 posix01 posix02 posix03 lease01
+bin_PROGRAMS = flock01 flock02 posix01 posix02 posix03 lease01 lease02
SUBDIRS = lib/
diff --git a/lease02.c b/lease02.c
new file mode 100644
index 0000000..0fa33e4
--- /dev/null
+++ b/lease02.c
@@ -0,0 +1,178 @@
+/*
+ * Lease performance test 2
+ *
+ * Fork off a given number of children who each open their own
+ * file. Then have each child take a read lease and release the lease
+ * for the given number of times.
+ *
+ * Time this to measure lease performance for lease heavy workloads where the
+ * locks are generally uncontended.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif /* HAVE_CONFIG_H */
+
+#include <stdio.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <stdlib.h>
+#include <time.h>
+#include <sys/mman.h>
+
+#include "timespec.h"
+
+#define NRPROC (128)
+#define NRLOCK (20480)
+
+static struct timespec *diff;
+
+static int
+leaseunlease(int nrlock, struct timespec *slot)
+{
+ int fd, i, ret;
+ pid_t pid = getpid();
+ char name[10]; /* big enough for pid_t in hex + NULL */
+ struct timespec start, end;
+
+ ret = snprintf(name, sizeof(name), "%x", pid);
+ if (ret >= (int)sizeof(name)) {
+ perror("sprintf");
+ return 1;
+ }
+
+ fd = open(name, O_CREAT|O_RDONLY, 0644);
+ if (fd < 0) {
+ perror("open");
+ return fd;
+ }
+
+ ret = clock_gettime(CLOCK_MONOTONIC_RAW, &start);
+ if (ret) {
+ perror("clock_gettime");
+ return ret;
+ }
+
+ for (i = 0; i < nrlock; ++i) {
+ ret = fcntl(fd, F_SETLEASE, F_RDLCK);
+ if (ret < 0) {
+ perror("fcntl");
+ break;
+ }
+ ret = fcntl(fd, F_SETLEASE, F_RDLCK);
+ if (ret < 0) {
+ perror("fcntl");
+ break;
+ }
+ }
+
+ ret = clock_gettime(CLOCK_MONOTONIC_RAW, &end);
+ if (ret) {
+ perror("clock_gettime");
+ return ret;
+ }
+
+ close(fd);
+ *slot = timespec_sub(end, start);
+ return ret;
+}
+
+void
+usage(char *prog)
+{
+ printf("usage: %s [-n nr_procs] [-l nr_locks] directory\n", prog);
+}
+
+int
+main(int argc, char **argv)
+{
+ int i, opt, valid = 0;
+ int nproc = NRPROC;
+ int nlock = NRLOCK;
+ pid_t *pids;
+ char *dirname;
+ struct timespec total = { .tv_sec = 0,
+ .tv_nsec = 0 };
+
+ while ((opt = getopt(argc, argv, "l:n:")) != -1) {
+ switch (opt) {
+ case 'l':
+ nlock = atoi(optarg);
+ break;
+ case 'n':
+ nproc = atoi(optarg);
+ break;
+ default:
+ usage(argv[0]);
+ return 1;
+ }
+ }
+
+ dirname = argv[optind];
+ if (!dirname) {
+ usage(argv[0]);
+ return 1;
+ }
+
+ if (mkdir(dirname, S_IRWXU)) {
+ perror("mkdir");
+ return 1;
+ }
+
+ if (chdir(dirname)) {
+ perror("chdir");
+ return 1;
+ }
+
+ pids = calloc(nproc, sizeof(pid_t));
+ if (!pids) {
+ fprintf(stderr, "Unable to allocate pids array!");
+ return 1;
+ }
+
+ diff = mmap(0, nproc * sizeof(*diff), PROT_READ | PROT_WRITE,
+ MAP_ANONYMOUS | MAP_SHARED, -1, 0);
+ if (diff == (struct timespec *)-1) {
+ fprintf(stderr, "Unable to allocate timespec array!");
+ return 1;
+ }
+
+ for (i = 0; i < nproc; ++i) {
+ pids[i] = fork();
+ if (!pids[i])
+ return leaseunlease(nlock, &diff[i]);
+ }
+
+ for (i = 0; i < nproc; ++i) {
+ int status;
+
+ if (pids[i] < 0) {
+ fprintf(stderr, "process %d failed to fork\n", i);
+ continue;
+ }
+ if (waitpid(pids[i], &status, 0) < 0) {
+ fprintf(stderr, "unable to reap pid %d\n", pids[i]);
+ continue;
+ }
+ if (!WIFEXITED(status) || WEXITSTATUS(status)) {
+ fprintf(stderr, "pid %d exited abnormally(0x%x)\n", pids[i],status);
+ continue;
+ }
+ total = timespec_add(total, diff[i]);
+ ++valid;
+ }
+
+ if (valid != nproc) {
+ fprintf(stderr, "Some children didn't run properly -- "
+ "requested %d but only got %d\n", nproc, valid);
+ return 1;
+ }
+
+ printf("%ld.%ld\n", total.tv_sec, total.tv_nsec);
+ return 0;
+}
--
2.1.0
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