Add a microbench mark which test the performance of taking and
releasing a read lease in a tight loop.
Based on posix01.
Signed-off-by: Daniel Wagner <daniel.wagner@xxxxxxxxxxxx>
---
Makefile.am | 2 +-
lease01.c | 177 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 178 insertions(+), 1 deletion(-)
create mode 100644 lease01.c
diff --git a/Makefile.am b/Makefile.am
index 2ece31b..b0a2851 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
+bin_PROGRAMS = flock01 flock02 posix01 posix02 posix03 lease01
SUBDIRS = lib/
diff --git a/lease01.c b/lease01.c
new file mode 100644
index 0000000..f3a2ae9
--- /dev/null
+++ b/lease01.c
@@ -0,0 +1,177 @@
+/*
+ * LEASE performance test 1
+ *
+ * Fork off a given number of children who attempt to repeatedly
+ * acquire a read lock over the whole file and then release it for a
+ * given number of times. Time this to get a rough indication of lease
+ * locking performance for a single, contended whole-file lock.
+ */
+
+#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 <stdbool.h>
+#include <sched.h>
+
+#include "timespec.h"
+
+#define NRPROC (128)
+#define NRLOCK (10240)
+
+static struct timespec *diff;
+
+static int
+leaseunlease(const char *name, int nrlock, struct timespec *slot,
+ bool verbose, bool yield)
+{
+ int fd, i, ret = 0;
+ struct timespec start, end;
+ pid_t pid = getpid();
+
+ 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");
+ return ret;
+ }
+
+ if (verbose)
+ printf("pid:%u\n", pid);
+
+ ret = fcntl(fd, F_SETLEASE, F_UNLCK);
+ ret = clock_gettime(CLOCK_MONOTONIC_RAW, &end);
+ if (ret) {
+ perror("clock_gettime");
+ return ret;
+ }
+
+ /* yield CPU to give another worker a chance */
+ if (yield)
+ sched_yield();
+ }
+
+ clock_gettime(CLOCK_MONOTONIC_RAW, &end);
+ if (ret) {
+ perror("clock_gettime");
+ return ret;
+ }
+
+ close(fd);
+ *slot = timespec_sub(end, start);
+
+ return 0;
+}
+
+void
+usage(char *prog)
+{
+ printf("usage: %s [-n nr_procs] [-l nr_locks] [-v] [-y] filename\n", prog);
+}
+
+int
+main(int argc, char **argv)
+{
+ bool verbose = false, yield = false;
+ int i, opt, valid = 0;
+ int nproc = NRPROC;
+ int nlock = NRLOCK;
+ pid_t *pids;
+ struct timespec total = { .tv_sec = 0,
+ .tv_nsec = 0 };
+
+
+ while ((opt = getopt(argc, argv, "l:n:vy")) != -1) {
+ switch (opt) {
+ case 'l':
+ nlock = atoi(optarg);
+ break;
+ case 'n':
+ nproc = atoi(optarg);
+ break;
+ case 'v':
+ verbose = true;
+ break;
+ default:
+ usage(argv[0]);
+ return 1;
+ }
+ }
+
+ if (!argv[optind]) {
+ usage(argv[0]);
+ 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(argv[optind], nlock,
+ &diff[i], verbose, yield);
+ }
+
+ 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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