diff --git a/c/zalloc_ext/std_string_speed_test.cpp b/c/zalloc_ext/std_string_speed_test.cpp
new file mode 100644
index 0000000..987d3e6
--- /dev/null
+++ b/c/zalloc_ext/std_string_speed_test.cpp
@@ -0,0 +1,49 @@
+//~ Success, iterations = 50000, nobj = 100000
+//~
+//~ real	0m0.818s
+//~ user	0m0.290s
+//~ sys	0m0.520s
+
+//~ при увеличении с 50000 до 60000 std::string лезут в своп, дождаться завершения не получится,
+//~ в то время как realloc(), xrealloc() и zrealloc() спокойно работают при кратном увеличении nobj.
+//~ во всех тестах zrealloc показала наилучшие результаты :), приблизительно в 1.5 раза быстрее xrealloc() и realloc().
+//~ std::string не у дел :(
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string>
+#include <vector>
+#include <string>
+
+int main(int argc, char *argv[])
+{
+	if (argc != 3) {
+		fputs("Usage: realloc_speed_test_cpp iterations nobj\n", stderr);
+		exit(-1);
+	}
+
+	size_t iterations = (size_t)atoi(argv[1]);
+	size_t nobj = (size_t)atoi(argv[2]);
+
+	std::vector<std::string> v(nobj);
+
+	//std::string app; for(size_t k=0; k<1000; k++) app += ' ';
+
+	size_t i, j, idx;
+	for (i = 0; i < iterations; i++) {
+		idx = (size_t)(rand() % (int)nobj);
+		try {
+			//v[idx] += v[idx];//app;
+			v[idx].resize(i);
+			//for (j = 0; j < i; j++)
+			//	v[idx] += ' ';
+		} catch(...) {
+			fprintf(stderr, "Alloc error at i = %lu\n", i);
+			exit(-1);
+		}
+	}
+
+	printf("Success, iterations = %lu, nobj = %lu\n", iterations, nobj);
+
+	return EXIT_SUCCESS;
+}
diff --git a/c/zalloc_ext/zalloc_speed_test_c.c b/c/zalloc_ext/zalloc_speed_test_c.c
new file mode 100644
index 0000000..ac361af
--- /dev/null
+++ b/c/zalloc_ext/zalloc_speed_test_c.c
@@ -0,0 +1,49 @@
+//~ time ./realloc_speed_test_c 50000 100000
+//~ Success, iterations = 50000, nobj = 100000
+//~
+//~ real	0m0.313s
+//~ user	0m0.130s
+//~ sys	0m0.160s
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "zalloc.h"
+#include "zalloc_ext.h"
+
+size_t optimal_zalloc_size(size_t size);
+
+int main(int argc, char *argv[])
+{
+	if (argc != 3) {
+		fputs("Usage: realloc_speed_test_cpp iterations nobj\n", stderr);
+		exit(-1);
+	}
+
+	size_t iterations = (size_t)atoi(argv[1]);
+	size_t nobj = (size_t)atoi(argv[2]);
+
+	void **p = malloc(sizeof(void *) * nobj);
+	memset(p, 0, sizeof(void *) * nobj);
+
+	//void *app = zmalloc(1000);
+
+	size_t i, j, idx;
+	for (i = 0; i < iterations; i++) {
+		idx = (size_t)(rand() % (int)nobj);
+		//p[idx] = zalloc_append(p[idx], p[idx]);
+		zrealloc_inplace(&p[idx], i);
+		//for (j = 0; j < i; j++)
+		//	p[idx] = zalloc_append8(p[idx], ' ');
+	}
+
+	for (i = 0; i < nobj; i++)
+		zfree(p[i]);
+
+	free(p);
+
+	printf("Success, iterations = %lu, nobj = %lu\n", iterations, nobj);
+
+	return EXIT_SUCCESS;
+}