[PATCH] Reduce thread stack size

[Bart Van Assche <bvanassche@acm.org>]

This patch reduces the stack size required by fio threads and hence allows
to run fio with 200 or more threads on systems with a moderate amount of
virtual memory.

Signed-off-by: Bart Van Assche <bart.vanassche@gmail.com>

diff --git a/fio.c b/fio.c
index 896f797..6ab0f4a 100644
--- a/fio.c
+++ b/fio.c
@@ -1380,9 +1380,13 @@ static void *gtod_thread_main(void *data)
 
 static int fio_start_gtod_thread(void)
 {
+	pthread_attr_t attr;
 	int ret;
 
-	ret = pthread_create(&gtod_thread, NULL, gtod_thread_main, NULL);
+	pthread_attr_init(&attr);
+	pthread_attr_setstacksize(&attr, PTHREAD_STACK_MIN);
+	ret = pthread_create(&gtod_thread, &attr, gtod_thread_main, NULL);
+	pthread_attr_destroy(&attr);
 	if (ret) {
 		log_err("Can't create gtod thread: %s\n", strerror(ret));
 		return 1;
diff --git a/verify.c b/verify.c
index 42ea462..7957bd4 100644
--- a/verify.c
+++ b/verify.c
@@ -886,12 +886,16 @@ done:
 int verify_async_init(struct thread_data *td)
 {
 	int i, ret;
+	pthread_attr_t attr;
+
+	pthread_attr_init(&attr);
+	pthread_attr_setstacksize(&attr, PTHREAD_STACK_MIN);
 
 	td->verify_thread_exit = 0;
 
 	td->verify_threads = malloc(sizeof(pthread_t) * td->o.verify_async);
 	for (i = 0; i < td->o.verify_async; i++) {
-		ret = pthread_create(&td->verify_threads[i], NULL,
+		ret = pthread_create(&td->verify_threads[i], &attr,
 					verify_async_thread, td);
 		if (ret) {
 			log_err("fio: async verify creation failed: %s\n",
@@ -907,6 +911,8 @@ int verify_async_init(struct thread_data *td)
 		td->nr_verify_threads++;
 	}
 
+	pthread_attr_destroy(&attr);
+
 	if (i != td->o.verify_async) {
 		log_err("fio: only %d verify threads started, exiting\n", i);
 		td->verify_thread_exit = 1;