diff --git a/src_main/containers/pimap.h b/src_main/containers/pimap.h
index 9b6333b9..c1b053a7 100644
--- a/src_main/containers/pimap.h
+++ b/src_main/containers/pimap.h
@@ -38,21 +38,36 @@ __PIVECTOR_SIMPLE_TYPE__(T)
 template<class T>
 void piQuickSort(T * a, ssize_t N) {
 	if (N < 1) return;
-	ssize_t i = 0, j = N;
-	T & p(a[N >> 1]);
-	do {
-		while (a[i] < p) i++;
-		while (a[j] > p) j--;
-		if (i <= j) {
-			if (i != j) {
-				//piCout << "swap" << i << j << a[i] << a[j];
-				piSwapBinary<T>(a[i], a[j]);
+	if (N < 47) {
+		T tmp;
+		ssize_t i,j;
+		for(i=1; i<N; i++) {
+			tmp = a[i];
+			j = i-1;
+			while(tmp<a[j] && j>=0)
+			{
+				a[j+1] = a[j];
+				j = j-1;
 			}
-			i++; j--;
+			a[j+1] = tmp;
 		}
-	} while (i <= j);
-	if (j > 0) piQuickSort(a, j);
-	if (N > i) piQuickSort(a + i, N - i);
+	} else {
+		ssize_t i = 0, j = N;
+		T & p(a[N >> 1]);
+		do {
+			while (a[i] < p) i++;
+			while (a[j] > p) j--;
+			if (i <= j) {
+				if (i != j) {
+					//piCout << "swap" << i << j << a[i] << a[j];
+					piSwapBinary<T>(a[i], a[j]);
+				}
+				i++; j--;
+			}
+		} while (i <= j);
+		if (j > 0) piQuickSort(a, j);
+		if (N > i) piQuickSort(a + i, N - i);
+	}
 }
 
 template <typename Key, typename T>