Add a small program to print data structure sizes.

Makefile.in

@@ -291,7 +291,8 @@ endif
 TESTS_STRESS := $(srcroot)test/stress/microbench.c \
 	$(srcroot)test/stress/fill_flush.c \
 	$(srcroot)test/stress/large_microbench.c \
-	$(srcroot)test/stress/hookbench.c
+	$(srcroot)test/stress/hookbench.c \
+	$(srcroot)test/stress/sizes.c
 
 
 TESTS := $(TESTS_UNIT) $(TESTS_INTEGRATION) $(TESTS_INTEGRATION_CPP) $(TESTS_STRESS)

test/stress/sizes.c

@@ -0,0 +1,50 @@
+#include "test/jemalloc_test.h"
+
+#include <stdio.h>
+
+/*
+ * Print the sizes of various important core data structures.  OK, I guess this
+ * isn't really a "stress" test, but it does give useful information about
+ * low-level performance characteristics, as the other things in this directory
+ * do.
+ */
+
+static void
+do_print(const char *name, size_t sz_bytes) {
+	const char *sizes[] = {"bytes", "KB", "MB", "GB", "TB", "PB", "EB",
+		"ZB"};
+	size_t sizes_max = sizeof(sizes)/sizeof(sizes[0]);
+
+	size_t ind = 0;
+	double sz = sz_bytes;
+	while (sz >= 1024 && ind < sizes_max) {
+		sz /= 1024;
+		ind++;
+	}
+	if (ind == 0) {
+		printf("%-20s: %zu bytes\n", name, sz_bytes);
+	} else {
+		printf("%-20s: %f %s\n", name, sz, sizes[ind]);
+	}
+}
+
+int
+main() {
+#define P(type)								\
+	do_print(#type, sizeof(type))
+	P(arena_t);
+	P(arena_stats_t);
+	P(base_t);
+	P(decay_t);
+	P(edata_t);
+	P(ecache_t);
+	P(eset_t);
+	P(malloc_mutex_t);
+	P(prof_tctx_t);
+	P(prof_gctx_t);
+	P(prof_tdata_t);
+	P(tcache_t);
+	P(tcache_slow_t);
+	P(tsd_t);
+#undef P
+}