toys

commit ab269344858660181fddd53b90e5a3f788f79aac
parent 027d9b04bb1fae62fbb1c842395ad1dacacc121f
Author: Mikołaj Lenczewski <mikolaj@lenczewski.org>
Date:   Tue,  9 Dec 2025 12:39:28 +0000

Update queue benchmark

Diffstat:
M
build.sh
 | 
2
+-
M
queue.c
 | 
28
+++++++++++++++++++---------

2 files changed, 20 insertions(+), 10 deletions(-)
diff --git a/build.sh b/build.sh
@@ -1,7 +1,7 @@
 #!/bin/sh
 
 WARNINGS="-Wall -Wextra -Wno-format-pedantic -Wno-unused-variable"
-FLAGS="$WARNINGS -std=c11 -O0 -g3"
+FLAGS="$WARNINGS -std=c11 -O3 -g3"
 
 set -ex
 
diff --git a/queue.c b/queue.c
@@ -15,8 +15,8 @@ writer(void *data)
 {
 	struct spsc_queue *queue = data;
 
+	size_t *ptr;
 	for (size_t i = 0; i < limit; i++) {
-		size_t *ptr;
 		do {
 			ptr = spsc_queue_write(queue, sizeof *ptr);
 		} while (!ptr);
@@ -26,7 +26,7 @@ writer(void *data)
 		spsc_queue_write_commit(queue, sizeof *ptr);
 	}
 
-	return NULL;
+	return (void *) (sizeof *ptr * limit); // return bytes written
 }
 
 static void *
@@ -34,8 +34,8 @@ reader(void *data)
 {
 	struct spsc_queue *queue = data;
 
+	size_t *ptr;
 	for (size_t i = 0; i < limit; i++) {
-		size_t *ptr;
 		do {
 			ptr = spsc_queue_read(queue, sizeof *ptr);
 		} while (!ptr);
@@ -45,7 +45,7 @@ reader(void *data)
 		spsc_queue_read_commit(queue, sizeof *ptr);
 	}
 
-	return NULL;
+	return (void *) (sizeof *ptr * limit); // return bytes read
 }
 
 static void
@@ -55,6 +55,7 @@ benchmark(void)
 	int res = spsc_queue_init(&queue, qsize, qsize);
 	assert(res == 0);
 
+	const uint64_t nsecs = 1000000000, usecs = 1000000, msecs = 1000;
 	struct timespec start, end;
 
 	pthread_t writer_thread, reader_thread;
@@ -63,16 +64,25 @@ benchmark(void)
 
 	clock_gettime(CLOCK_MONOTONIC_RAW, &start);
 
-	pthread_join(writer_thread, NULL);
-	pthread_join(reader_thread, NULL);
+	void *nbytes_written;
+	pthread_join(writer_thread, &nbytes_written);
+
+	void *nbytes_read;
+	pthread_join(reader_thread, &nbytes_read);
 
 	clock_gettime(CLOCK_MONOTONIC_RAW, &end);
 
-	uint64_t ns = ((end.tv_sec - start.tv_sec) * 1000000000) + (end.tv_nsec - start.tv_nsec);
+	uint64_t ns = ((end.tv_sec - start.tv_sec) * nsecs) + (end.tv_nsec - start.tv_nsec);
+	uint64_t bytes = (uint64_t) nbytes_written + (uint64_t) nbytes_read;
+	double gigs = bytes / (double) GiB(1);
 
 	printf("Iters: %zu\n", limit);
-	printf("Elapsed time: ms: %lu, ns: %lu\n", ns / 1000000, ns);
-	printf("Ops/sec: %lu\n", (limit * 1000000000) / ns);
+	printf("Elapsed time: ms: %lu, ns: %lu, avg. ns per iter: %lu\n",
+			ns / usecs, ns, ns / limit);
+
+	printf("Ops/sec: %lu, bytes written: %lu, bytes read: %lu, total GiBps: %.03f\n",
+			(limit * nsecs) / ns, (uint64_t) nbytes_written, (uint64_t) nbytes_read,
+			(float) ((gigs * nsecs) / ns));
 }
 
 int