[PATCH] Benchtests: Improve large memcpy/memset benchmarks

[Wilco Dijkstra]

Adjust sizes between 64KB and 16MB and iterations based on length. 
Remove incorrect uses of alloc_bufs (since we're not interested in measuring
Linux clear_page time).

OK for commit?

---

diff --git a/benchtests/bench-bzero-large.c b/benchtests/bench-bzero-large.c
index 7076c0a17b00d76c26aa6adb4c3cc0aedcf69955..dea414ec8d1bb160409725996244178ee4fa93fd 100644
--- a/benchtests/bench-bzero-large.c
+++ b/benchtests/bench-bzero-large.c
@@ -22,9 +22,8 @@
 #else
 # define TEST_NAME "bzero"
 #endif
-#define START_SIZE (128 * 1024)
-#define MIN_PAGE_SIZE (getpagesize () + 64 * 1024 * 1024)
-#define TIMEOUT (20 * 60)
+#define START_SIZE (64 * 1024)
+#define MIN_PAGE_SIZE (getpagesize () + 16 * 1024 * 1024)
 #include "bench-string.h"
 
 #include "json-lib.h"
@@ -52,7 +51,7 @@ IMPL (memset_zero, 0)
 static void
 do_one_test (json_ctx_t *json_ctx, impl_t *impl, CHAR *s, size_t n)
 {
-  size_t i, iters = 16;
+  size_t i, iters = (MIN_PAGE_SIZE * 64) / n;
   timing_t start, stop, cur;
 
   TIMING_NOW (start);
@@ -74,20 +73,13 @@ do_one_test (json_ctx_t *json_ctx, impl_t *impl, CHAR *s, size_t n)
 static void
 do_test (json_ctx_t *json_ctx, size_t align, size_t len)
 {
-  align &= 63;
-  if ((align + len) * sizeof (CHAR) > page_size)
-    return;
-
   json_element_object_begin (json_ctx);
   json_attr_uint (json_ctx, "length", len);
   json_attr_uint (json_ctx, "alignment", align);
   json_array_begin (json_ctx, "timings");
 
   FOR_EACH_IMPL (impl, 0)
-    {
-      do_one_test (json_ctx, impl, (CHAR *) (buf1) + align, len);
-      alloc_bufs ();
-    }
+    do_one_test (json_ctx, impl, (CHAR *) (buf1) + align, len);
 
   json_array_end (json_ctx);
   json_element_object_end (json_ctx);
diff --git a/benchtests/bench-memcpy-large.c b/benchtests/bench-memcpy-large.c
index 7b2c5530af3883acc4b3895cb11667e6ff1a55ff..9e544a4729197f886f6cb092ec225004b586d197 100644
--- a/benchtests/bench-memcpy-large.c
+++ b/benchtests/bench-memcpy-large.c
@@ -19,10 +19,9 @@
 #ifndef MEMCPY_RESULT
 # define MEMCPY_RESULT(dst, len) dst
 # define START_SIZE (64 * 1024)
-# define MIN_PAGE_SIZE (getpagesize () + 32 * 1024 * 1024)
+# define MIN_PAGE_SIZE (getpagesize () + 16 * 1024 * 1024)
 # define TEST_MAIN
 # define TEST_NAME "memcpy"
-# define TIMEOUT (20 * 60)
 # include "bench-string.h"
 
 IMPL (memcpy, 1)
@@ -36,7 +35,7 @@ static void
 do_one_test (json_ctx_t *json_ctx, impl_t *impl, char *dst, const char *src,
 	     size_t len)
 {
-  size_t i, iters = 16;
+  size_t i, iters = (MIN_PAGE_SIZE * 8) / len;
   timing_t start, stop, cur;
 
   TIMING_NOW (start);
@@ -59,12 +58,7 @@ do_test (json_ctx_t *json_ctx, size_t align1, size_t align2, size_t len,
   char *s1, *s2;
   size_t repeats;
   align1 &= 4095;
-  if (align1 + len >= page_size)
-    return;
-
   align2 &= 4095;
-  if (align2 + len >= page_size)
-    return;
 
   s1 = (char *) (buf1 + align1);
   s2 = (char *) (buf2 + align2);
diff --git a/benchtests/bench-memmove-large.c b/benchtests/bench-memmove-large.c
index a09dd3678848a3bf8612732439700eb8ef5d82ea..fd504653f681b172800cc34e054cc745180aa4fa 100644
--- a/benchtests/bench-memmove-large.c
+++ b/benchtests/bench-memmove-large.c
@@ -16,12 +16,10 @@
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#define BASE_PAGE_SIZE (1024 * 1024)
-#define START_SIZE (4 * 1024)
+#define START_SIZE (64 * 1024)
 #define MIN_PAGE_SIZE (getpagesize () + 16 * 1024 * 1024)
 #define TEST_MAIN
 #define TEST_NAME "memmove"
-#define TIMEOUT (20 * 60)
 #include "bench-string.h"
 #include "json-lib.h"
 
@@ -33,7 +31,7 @@ static void
 do_one_test (json_ctx_t *json_ctx, impl_t *impl, char *dst, char *src,
 	     size_t len)
 {
-  size_t i, iters = 16;
+  size_t i, iters = (MIN_PAGE_SIZE * 8) / len;
   timing_t start, stop, cur;
 
   TIMING_NOW (start);
@@ -54,13 +52,8 @@ do_test (json_ctx_t *json_ctx, size_t align1, size_t align2, size_t len)
   size_t i, j;
   char *s1, *s2;
 
-  align1 &= 127;
-  if (align1 + len >= page_size)
-    return;
-
-  align2 &= 127;
-  if (align2 + len >= page_size)
-    return;
+  align1 &= 4095;
+  align2 &= 4095;
 
   s1 = (char *) (buf2 + align1);
   s2 = (char *) (buf2 + align2);
diff --git a/benchtests/bench-memset-large.c b/benchtests/bench-memset-large.c
index a1f33245d4960c1e82fc441b5faf322204035202..c3f9ee0cd75d3cb30f8b3df15672f895c111fc28 100644
--- a/benchtests/bench-memset-large.c
+++ b/benchtests/bench-memset-large.c
@@ -18,9 +18,8 @@
 
 #define TEST_MAIN
 #define TEST_NAME "memset"
-#define START_SIZE (128 * 1024)
-#define MIN_PAGE_SIZE (getpagesize () + 64 * 1024 * 1024)
-#define TIMEOUT (20 * 60)
+#define START_SIZE (64 * 1024)
+#define MIN_PAGE_SIZE (getpagesize () + 16 * 1024 * 1024)
 #include "bench-string.h"
 
 #include "json-lib.h"
@@ -35,7 +34,7 @@ static void
 do_one_test (json_ctx_t *json_ctx, impl_t *impl, CHAR *s,
 	     int c __attribute ((unused)), size_t n)
 {
-  size_t i, iters = 16;
+  size_t i, iters = (MIN_PAGE_SIZE * 64) / n;
   timing_t start, stop, cur;
 
   TIMING_NOW (start);
@@ -53,10 +52,6 @@ do_one_test (json_ctx_t *json_ctx, impl_t *impl, CHAR *s,
 static void
 do_test (json_ctx_t *json_ctx, size_t align, int c, size_t len)
 {
-  align &= 63;
-  if ((align + len) * sizeof (CHAR) > page_size)
-    return;
-
   json_element_object_begin (json_ctx);
   json_attr_uint (json_ctx, "length", len);
   json_attr_uint (json_ctx, "alignment", align);
@@ -64,10 +59,7 @@ do_test (json_ctx_t *json_ctx, size_t align, int c, size_t len)
   json_array_begin (json_ctx, "timings");
 
   FOR_EACH_IMPL (impl, 0)
-    {
-      do_one_test (json_ctx, impl, (CHAR *) (buf1) + align, c, len);
-      alloc_bufs ();
-    }
+    do_one_test (json_ctx, impl, (CHAR *) (buf1) + align, c, len);
 
   json_array_end (json_ctx);
   json_element_object_end (json_ctx);