update stress test with more documentation
@@ -5,8 +5,13 @@ terms of the MIT license.
-----------------------------------------------------------------------------*/
/* This is a stress test for the allocator, using multiple threads and
- transferring objects between threads. This is not a typical workload
- but uses a random linear size distribution. Timing can also depend on
+ transferring objects between threads. It tries to reflect real-world workloads:
+ - allocation size is distributed linearly in powers of two
+ - with some fraction extra large (and some extra extra large)
+ - the allocations are initialized and read again at free
+ - pointers transfer between threads
+ - threads are terminated and recreated with some objects surviving in between
+ - uses deterministic "randomness", but execution can still depend on
(random) thread scheduling. Do not use this test as a benchmark!
*/
@@ -22,13 +27,13 @@ terms of the MIT license.
// argument defaults
static int THREADS = 32; // more repeatable if THREADS <= #processors
static int SCALE = 50; // scaling factor
-static int ITER = 10; // N full iterations re-creating all threads
+static int ITER = 10; // N full iterations destructing and re-creating all threads
// static int THREADS = 8; // more repeatable if THREADS <= #processors
// static int SCALE = 100; // scaling factor
static bool allow_large_objects = true; // allow very large objects?
-static size_t use_one_size = 0; // use single object size of N uintptr_t?
+static size_t use_one_size = 0; // use single object size of `N * sizeof(uintptr_t)`?
#ifdef USE_STD_MALLOC
@@ -185,7 +190,7 @@ int main(int argc, char** argv) {
long n = (strtol(argv[3], &end, 10));
if (n > 0) ITER = n;
}
- printf("start with %d threads with a %d%% load-per-thread and %d iterations\n", THREADS, SCALE, ITER);
+ printf("Using %d threads with a %d%% load-per-thread and %d iterations\n", THREADS, SCALE, ITER);
//int res = mi_reserve_huge_os_pages(4,1);
//printf("(reserve huge: %i\n)", res);
@@ -204,7 +209,7 @@ int main(int argc, char** argv) {
}
mi_collect(false);
#ifndef NDEBUG
- if ((n + 1) % 10 == 0) { printf("- iterations: %3d\n", n + 1); }
+ if ((n + 1) % 10 == 0) { printf("- iterations left: %3d\n", ITER - n + 1); }
#endif
}
