diff --git a/src/brz.c b/src/brz.c
index 195195d..91df769 100755
--- a/src/brz.c
+++ b/src/brz.c
@@ -68,7 +68,7 @@ void brz_config_set_hashfuncs(cmph_config_t *mph, CMPH_HASH *hashfuncs)
 void brz_config_set_memory_availability(cmph_config_t *mph, cmph_uint32 memory_availability)
 {
 	brz_config_data_t *brz = (brz_config_data_t *)mph->data;
-	brz->memory_availability = memory_availability*1024*1024;
+	if(memory_availability > 0) brz->memory_availability = memory_availability*1024*1024;
 }
 
 void brz_config_set_tmp_dir(cmph_config_t *mph, cmph_uint8 *tmp_dir)
diff --git a/src/brz.h b/src/brz.h
index 886eab2..e1c932e 100644
--- a/src/brz.h
+++ b/src/brz.h
@@ -9,6 +9,7 @@ typedef struct __brz_config_data_t brz_config_data_t;
 brz_config_data_t *brz_config_new();
 void brz_config_set_hashfuncs(cmph_config_t *mph, CMPH_HASH *hashfuncs);
 void brz_config_set_tmp_dir(cmph_config_t *mph, cmph_uint8 *tmp_dir);
+void brz_config_set_memory_availability(cmph_config_t *mph, cmph_uint32 memory_availability);
 void brz_config_destroy(cmph_config_t *mph);
 cmph_t *brz_new(cmph_config_t *mph, float c);
 
diff --git a/src/cmph.c b/src/cmph.c
index 30bee18..9f0b464 100644
--- a/src/cmph.c
+++ b/src/cmph.c
@@ -204,6 +204,25 @@ void cmph_config_set_tmp_dir(cmph_config_t *mph, cmph_uint8 *tmp_dir)
 
 }
 
+void cmph_config_set_memory_availability(cmph_config_t *mph, cmph_uint32 memory_availability)
+{
+	switch (mph->algo)
+	{
+		case CMPH_CHM:
+			break;
+		case CMPH_BMZ: /* included -- Fabiano */
+			break;
+		case CMPH_BMZ8: /* included -- Fabiano */
+			break;
+		case CMPH_BRZ: /* included -- Fabiano */
+			brz_config_set_memory_availability(mph, memory_availability);
+			break;
+		default:
+			assert(0);
+	}
+
+}
+
 void cmph_config_destroy(cmph_config_t *mph)
 {
 	DEBUGP("Destroying mph with algo %s\n", cmph_names[mph->algo]);
diff --git a/src/cmph.h b/src/cmph.h
index c301a91..88ed317 100644
--- a/src/cmph.h
+++ b/src/cmph.h
@@ -36,6 +36,7 @@ void cmph_config_set_verbosity(cmph_config_t *mph, cmph_uint32 verbosity);
 void cmph_config_set_graphsize(cmph_config_t *mph, float c);
 void cmph_config_set_algo(cmph_config_t *mph, CMPH_ALGO algo);
 void cmph_config_set_tmp_dir(cmph_config_t *mph, cmph_uint8 *tmp_dir);
+void cmph_config_set_memory_availability(cmph_config_t *mph, cmph_uint32 memory_availability);
 void cmph_config_destroy(cmph_config_t *mph);
 
 /** Hash API **/
diff --git a/src/main.c b/src/main.c
index 6416359..5694108 100644
--- a/src/main.c
+++ b/src/main.c
@@ -22,12 +22,12 @@
 
 void usage(const char *prg)
 {
-	fprintf(stderr, "usage: %s [-v] [-h] [-V] [-k nkeys] [-f hash_function] [-g [-c value][-s seed] ] [-a algorithm] [-d tmp_dir] [-m file.mph]  keysfile\n", prg);   
+	fprintf(stderr, "usage: %s [-v] [-h] [-V] [-k nkeys] [-f hash_function] [-g [-c value][-s seed] ] [-a algorithm] [-M memory_in_MB] [-d tmp_dir] [-m file.mph]  keysfile\n", prg);   
 }
 void usage_long(const char *prg)
 {
 	cmph_uint32 i;
-	fprintf(stderr, "usage: %s [-v] [-h] [-V] [-k nkeys] [-f hash_function] [-g [-c value][-s seed] ] [-a algorithm] [-d tmp_dir] [-m file.mph] keysfile\n", prg);   
+	fprintf(stderr, "usage: %s [-v] [-h] [-V] [-k nkeys] [-f hash_function] [-g [-c value][-s seed] ] [-a algorithm] [-M memory_in_MB] [-d tmp_dir] [-m file.mph] keysfile\n", prg);   
 	fprintf(stderr, "Minimum perfect hashing tool\n\n"); 
 	fprintf(stderr, "  -h\t print this help message\n");
 	fprintf(stderr, "  -c\t c value that determines the number of vertices in the graph\n");
@@ -41,6 +41,7 @@ void usage_long(const char *prg)
 	fprintf(stderr, "  -g\t generation mode\n");
 	fprintf(stderr, "  -s\t random seed\n");
 	fprintf(stderr, "  -m\t minimum perfect hash function file \n");
+	fprintf(stderr, "  -M\t main memory availability (in MB)\n");
 	fprintf(stderr, "  -d\t temporary directory used in brz algorithm \n");
 	fprintf(stderr, "  keysfile\t line separated file with keys\n");
 }
@@ -65,10 +66,10 @@ int main(int argc, char **argv)
 	cmph_t *mphf = NULL;
 	cmph_uint8 * tmp_dir = NULL;
 	cmph_io_adapter_t *source;
-
+	cmph_uint32 memory_availability = 0;
 	while (1)
 	{
-		char ch = getopt(argc, argv, "hVvgc:k:a:f:m:d:s:");
+		char ch = getopt(argc, argv, "hVvgc:k:a:M:f:m:d:s:");
 		if (ch == -1) break;
 		switch (ch)
 		{
@@ -111,6 +112,16 @@ int main(int argc, char **argv)
 			case 'd':
 				tmp_dir = strdup(optarg);
 				break;
+			case 'M':
+				{
+					char *cptr;
+					memory_availability = strtoul(optarg, &cptr, 10);
+					if(*cptr != 0) {
+						fprintf(stderr, "Invalid memory availability %s\n", optarg);
+						exit(1);
+					}
+				}
+				break;
 			case 'v':
 				++verbosity;
 				break;
@@ -202,6 +213,7 @@ int main(int argc, char **argv)
 		if (nhashes) cmph_config_set_hashfuncs(config, hashes);
 		cmph_config_set_verbosity(config, verbosity);
 		cmph_config_set_tmp_dir(config, tmp_dir);
+		cmph_config_set_memory_availability(config, memory_availability);
 		if(mph_algo == CMPH_BMZ && c >= 2.0) c=1.15;
 		if (c != 0) cmph_config_set_graphsize(config, c);
 		mphf = cmph_new(config);