diff --git a/ut.c b/ut.c
index 9179f6658e7..6bd60fbaeb8 100644
--- a/ut.c
+++ b/ut.c
@@ -30,6 +30,7 @@
 #include <grp.h>
 #include "ut.h"
 
+unsigned int int2str_buf_index = 0;
 char int2str_buf[INT2STR_BUF_NO][INT2STR_MAX_LEN];
 
 int tcp_timeout_con_get = 0;
diff --git a/ut.h b/ut.h
index 60ca58160ae..4323b884855 100644
--- a/ut.h
+++ b/ut.h
@@ -271,13 +271,15 @@ static inline char* int2bstr(uint64_t l, char *s, int* len)
 /* INTeger-TO-STRing : convers a 64-bit integer to a string
  * returns a pointer to a static buffer containing l in asciiz & sets len */
 #define INT2STR_BUF_NO    7
+extern unsigned int int2str_buf_index;
 extern char int2str_buf[INT2STR_BUF_NO][INT2STR_MAX_LEN];
+static inline unsigned int getstrbufindex() {
+	return ((int2str_buf_index++) % INT2STR_BUF_NO);
+}
+
 static inline char* int2str(uint64_t l, int* len)
 {
-	static unsigned int it = 0;
-
-	if ((++it)==INT2STR_BUF_NO) it = 0;
-	return int2bstr( l, int2str_buf[it], len);
+	return int2bstr( l, int2str_buf[getstrbufindex()], len);
 }
 
 
@@ -303,9 +305,9 @@ static inline char* sint2str(long l, int* len)
 
 static inline char* double2str(double d, int* len)
 {
-	static int buf;
+	unsigned int buf;
 
-	buf = (buf + 1) % INT2STR_BUF_NO;
+	buf = getstrbufindex();
 	*len = snprintf(int2str_buf[buf], INT2STR_MAX_LEN - 1, "%0.*lf",
 	                FLOATING_POINT_PRECISION, d);
 	int2str_buf[buf][*len] = '\0';