X-Git-Url: http://git.ozlabs.org/?p=ccan;a=blobdiff_plain;f=ccan%2Ftimer%2Fbenchmarks%2Fexpected-usage.c;fp=ccan%2Ftimer%2Fbenchmarks%2Fexpected-usage.c;h=9777856550ec2eb2bdec25bc63567bfcb6d77513;hp=0000000000000000000000000000000000000000;hb=606cca7b0ed5236d1df1c4436ca79db6e3fd5321;hpb=c289035bc960c7316208133cc44bf6f968498613

diff --git a/ccan/timer/benchmarks/expected-usage.c b/ccan/timer/benchmarks/expected-usage.c
new file mode 100644
index 00000000..97778565
--- /dev/null
+++ b/ccan/timer/benchmarks/expected-usage.c
@@ -0,0 +1,71 @@
+/* We expect a timer to rarely go off, so benchmark that case:
+ * Every 1ms a connection comes in, we set up a 30 second timer for it.
+ * After 8192ms we finish the connection (and thus delete the timer).
+ */
+#include <ccan/timer/timer.h>
+#include <ccan/opt/opt.h>
+#include <ccan/array_size/array_size.h>
+#include <stdio.h>
+
+#define PER_CONN_TIME 8192
+#define CONN_TIMEOUT_MS 30000
+
+int main(int argc, char *argv[])
+{
+	struct timespec start, curr;
+	struct timers timers;
+	struct list_head expired;
+	struct timer t[PER_CONN_TIME];
+	unsigned int i, num;
+	bool check = false;
+
+	opt_register_noarg("-c|--check", opt_set_bool, &check,
+			   "Check timer structure during progress");
+
+	opt_parse(&argc, argv, opt_log_stderr_exit);
+
+	num = argv[1] ? atoi(argv[1]) : (check ? 10000 : 1000000);
+
+	list_head_init(&expired);
+	curr = start = time_now();
+	timers_init(&timers, start);
+
+	for (i = 0; i < num; i++) {
+		curr = time_add(curr, time_from_msec(1));
+		if (check)
+			timers_check(&timers, NULL);
+		timers_expire(&timers, curr, &expired);
+		if (check)
+			timers_check(&timers, NULL);
+		assert(list_empty(&expired));
+
+		if (i >= PER_CONN_TIME) {
+			timer_del(&timers, &t[i%PER_CONN_TIME]);
+			if (check)
+				timers_check(&timers, NULL);
+		}
+		timer_add(&timers, &t[i%PER_CONN_TIME],
+			  time_add(curr, time_from_msec(CONN_TIMEOUT_MS)));
+		if (check)
+			timers_check(&timers, NULL);
+	}
+	if (num > PER_CONN_TIME) {
+		for (i = 0; i < PER_CONN_TIME; i++)
+			timer_del(&timers, &t[i]);
+	}
+
+	curr = time_sub(time_now(), start);
+	if (check)
+		timers_check(&timers, NULL);
+	timers_cleanup(&timers);
+	opt_free_table();
+
+	for (i = 0; i < ARRAY_SIZE(timers.level); i++)
+		if (!timers.level[i])
+			break;
+
+	printf("%u in %lu.%09lu (%u levels / %zu)\n",
+	       num, (long)curr.tv_sec, curr.tv_nsec,
+	       i, ARRAY_SIZE(timers.level));
+	return 0;
+}