libpthread-137.1.1.tar.gz

[apple/libpthread.git] / tests / maxwidth.c

diff --git a/tests/maxwidth.c b/tests/maxwidth.c
new file mode 100644 (file)
index 0000000..9c1dd04
--- /dev/null
+++ b/tests/maxwidth.c
@@ -0,0 +1,97 @@
+#include <dispatch/dispatch.h>
+#include <dispatch/private.h>
+#include <stdio.h>
+
+#define NUM 100000
+static volatile size_t concur;
+static volatile size_t final;
+dispatch_queue_t resultsq;
+dispatch_group_t rgroup;
+
+void finish(void* ctxt)
+{
+       int c = (uintptr_t)ctxt;
+       if (c > final) final = c;
+}
+
+void work(void* ctxt)
+{
+       int c = __sync_add_and_fetch(&concur, 1);
+       if (ctxt) {
+               usleep(1000);
+       } else {
+               for (int i=0; i<100000; i++) {
+                       __asm__ __volatile__ ("");
+               }
+       }
+       dispatch_group_async_f(rgroup, resultsq, (void*)(uintptr_t)c, finish);
+       __sync_sub_and_fetch(&concur, 1);
+}
+
+int main(int argc, const char *argv[])
+{
+       size_t i;
+
+       rgroup = dispatch_group_create();
+       resultsq = dispatch_queue_create("results", 0);
+       dispatch_suspend(resultsq);
+
+       dispatch_group_t group = dispatch_group_create();
+
+       final = concur = 0;
+       for (i=0; i<NUM; i++) {
+               dispatch_group_async_f(group, dispatch_get_global_queue(0, 0), NULL, work);
+       }
+
+       dispatch_group_wait(group, DISPATCH_TIME_FOREVER);
+       dispatch_resume(resultsq);
+
+       dispatch_group_wait(rgroup, DISPATCH_TIME_FOREVER);
+       printf("max concurrency: %zd threads.\n", final);
+
+       dispatch_suspend(resultsq);
+       
+       /* ******* */
+
+       final = concur = 0;
+       for (i=0; i<NUM; i++) {
+               dispatch_group_async_f(group, dispatch_get_global_queue(0, 0), (void*)1, work);
+       }
+
+       dispatch_group_wait(group, DISPATCH_TIME_FOREVER);
+       dispatch_resume(resultsq);
+
+       dispatch_group_wait(rgroup, DISPATCH_TIME_FOREVER);
+       printf("max blocking concurrency: %zd threads.\n", final);
+
+       dispatch_suspend(resultsq);
+
+       /* ******* */
+
+       final = concur = 0;
+       for (i=0; i<NUM; i++) {
+               dispatch_group_async_f(group, dispatch_get_global_queue(0, DISPATCH_QUEUE_OVERCOMMIT), NULL, work);
+       }
+
+       dispatch_group_wait(group, DISPATCH_TIME_FOREVER);
+       dispatch_resume(resultsq);
+
+       dispatch_group_wait(rgroup, DISPATCH_TIME_FOREVER);
+       printf("max overcommit concurrency: %zd threads.\n", final);
+       dispatch_suspend(resultsq);
+
+       /* ******* */
+
+       final = concur = 0;
+       for (i=0; i<NUM; i++) {
+               dispatch_group_async_f(group, dispatch_get_global_queue(0, DISPATCH_QUEUE_OVERCOMMIT), (void*)1, work);
+       }
+
+       dispatch_group_wait(group, DISPATCH_TIME_FOREVER);
+       dispatch_resume(resultsq);
+
+       dispatch_group_wait(rgroup, DISPATCH_TIME_FOREVER);
+       printf("max blocking overcommit concurrency: %zd threads.\n", final);
+
+       return 0;
+}