benchmark: add a benchmark for bgo/760267

Big suprise - GstStructure is faster than GVariant.

tests/benchmarks/.gitignore

@@ -9,4 +9,5 @@ gstclockstress
 gstpollstress
 gstpoolstress
 mass-elements
+tracerserialize
 *.gcno

tests/benchmarks/Makefile.am

@@ -8,7 +8,8 @@ noinst_PROGRAMS = \
         gstpollstress \
         gstpoolstress \
         gstclockstress	\
-	gstbufferstress
+        gstbufferstress \
+        tracerserialize
 
 LDADD = $(GST_OBJ_LIBS)
 AM_CFLAGS = $(GST_OBJ_CFLAGS)

tests/benchmarks/tracerserialize.c

@@ -0,0 +1,92 @@
+/* GStreamer
+ * Copyright (C) 2016 Stefan Sauer <ensonic@users.sf.net>
+ *
+ * caps.c: benchmark for caps creation and destruction
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITcreating %d capsNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
+ */
+
+/* to check the sizes run:
+ *
+ * GST_DEBUG="default:7" GST_DEBUG_FILE=trace.log ./tracerserialize
+ *
+ * grep "log_gst_structure" trace.log >tracerserialize.gststructure.log
+ * grep "log_g_variant" trace.log >tracerserialize.gvariant.log
+ *
+ */
+
+#include <gst/gst.h>
+
+#define NUM_LOOPS 100000
+
+static void
+log_gst_structure (const gchar * name, const gchar * first, ...)
+{
+  va_list var_args;
+  GstStructure *s;
+  gchar *l;
+
+  va_start (var_args, first);
+  s = gst_structure_new_valist (name, first, var_args);
+  l = gst_structure_to_string (s);
+  GST_TRACE ("%s", l);
+  g_free (l);
+  gst_structure_free (s);
+  va_end (var_args);
+}
+
+static void
+log_g_variant (const gchar * format, ...)
+{
+  va_list var_args;
+  GVariant *v;
+  gchar *l;
+
+  va_start (var_args, format);
+  v = g_variant_new_va (format, NULL, &var_args);
+  l = g_variant_print (v, FALSE);
+  GST_TRACE ("%s", l);
+  g_free (l);
+  g_variant_unref (v);
+  va_end (var_args);
+}
+
+gint
+main (gint argc, gchar * argv[])
+{
+  GstClockTime start, end;
+  gint i;
+
+  gst_init (&argc, &argv);
+
+  start = gst_util_get_timestamp ();
+  for (i = 0; i < NUM_LOOPS; i++) {
+    log_gst_structure ("name",
+        "ts", G_TYPE_UINT64, (guint64) 0,
+        "index", G_TYPE_UINT, 10,
+        "test", G_TYPE_STRING, "hallo",
+        "flag", GST_TYPE_PAD_DIRECTION, GST_PAD_SRC, NULL);
+  }
+  end = gst_util_get_timestamp ();
+  g_print ("%" GST_TIME_FORMAT ": GstStructure\n", GST_TIME_ARGS (end - start));
+
+  start = gst_util_get_timestamp ();
+  for (i = 0; i < NUM_LOOPS; i++) {
+    log_g_variant ("(stusu)", "name", (guint64) 0, 10, "hallo", GST_PAD_SRC);
+  }
+  end = gst_util_get_timestamp ();
+  g_print ("%" GST_TIME_FORMAT ": GVariant\n", GST_TIME_ARGS (end - start));
+}