diff --git a/.gitignore b/.gitignore
index c3ba4cd..e549ed7 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,6 +2,8 @@
 libft_malloc*
 test
 gpttest
+a.out
+tester
 # Prerequisites
 *.d
 
diff --git a/Makefile b/Makefile
index 4139e25..361be4f 100644
--- a/Makefile
+++ b/Makefile
@@ -39,8 +39,8 @@ re: fclean all
 rere: ffclean all
 
 test: $(NAME)
-	$(CC) $(CFLAGS) -o test test.c -L. -lft_malloc -Wl,-rpath=.
-	$(CC) $(CFLAGS) -o gpttest gpttest.c -L. -lft_malloc -Wl,-rpath=.
+	$(CC) $(CFLAGS) -O0 -o test test.c -L. -lft_malloc -Wl,-rpath=.
+	$(CC) $(CFLAGS) -O0 -o gpttest gpttest.c -L. -lft_malloc -Wl,-rpath=.
 
 $(LIBFT):
 	make -C libft
diff --git a/include/malloc.h b/include/malloc.h
index 638f594..8c859a8 100644
--- a/include/malloc.h
+++ b/include/malloc.h
@@ -12,6 +12,7 @@
 #define MMAP_SHIFT(mmap) ((void *)mmap + sizeof(t_mmap))
 #define ALLOC_SHIFT(alloc) ((void *)alloc + sizeof(t_alloc))
 
+#define ALIGNMENT 16
 #define TINY_MMAP_SIZE (4 * getpagesize())
 #define TINY_ALLOC_SIZE (128)
 #define SMALL_MMAP_SIZE (32 * getpagesize())
diff --git a/src/alloc.c b/src/alloc.c
index 537c747..ca38c3e 100644
--- a/src/alloc.c
+++ b/src/alloc.c
@@ -1,11 +1,17 @@
 #include "../include/malloc.h"
 
+void *alignp(void *size) {
+  intptr_t s = (intptr_t)size;
+  while (s % ALIGNMENT != 0)
+    s++;
+  /* ft_printf("before %p, after %p\n", size, (void *)s); */
+  return (void *)s;
+}
+
 t_alloc *new_alloc(t_mmap *mmap, void *ptr, size_t size) {
   t_alloc *alloc = ptr;
   alloc->size = size;
   alloc->parent = mmap;
-  /* ft_printf("creating new alloc at %p. should return %p\n", ptr, */
-  /* ALLOC_SHIFT(ptr)); */
   alloc->next = NULL;
   alloc->prev = NULL;
 
@@ -34,24 +40,26 @@ t_alloc *new_alloc(t_mmap *mmap, void *ptr, size_t size) {
 }
 
 t_alloc *find_alloc(size_t size) {
+  size += ALIGNMENT; // add space to align the return ptr
   if (!g_mmap)
     return NULL;
   for (t_mmap *mmap = g_mmap; mmap; mmap = mmap->next) {
-    if (mmap->type != get_mmap_type(size))
+    if (mmap->type != get_mmap_type(size - ALIGNMENT))
       continue;
 
     // in case it's the first allocation of a mmap
     if (!mmap->alloc)
-      return new_alloc(mmap, MMAP_SHIFT(mmap), size);
+      return new_alloc(mmap, alignp(MMAP_SHIFT(mmap)), size);
+    /* return new_alloc(mmap, MMAP_SHIFT(mmap), size); */
 
     t_alloc *alloc = mmap->alloc;
-    void *ptr = MMAP_SHIFT(mmap);
+    void *ptr = alignp(MMAP_SHIFT(mmap));
     while (alloc) { // seach for space between allocated spaces
       size_t space = (void *)alloc - ptr;
       if (ptr < (void *)alloc && space >= (size_t)ALLOC_SHIFT(size))
         return new_alloc(mmap, ptr, size);
 
-      ptr = ALLOC_SHIFT(alloc) + alloc->size;
+      ptr = alignp(ALLOC_SHIFT(alloc) + alloc->size);
       alloc = alloc->next;
     }
     // allocated space after the last allocated space
diff --git a/src/calloc.c b/src/calloc.c
index 2acc623..4c7706b 100644
--- a/src/calloc.c
+++ b/src/calloc.c
@@ -2,22 +2,19 @@
 
 void *calloc(size_t nmemb, size_t size) {
   ft_printf("calloc(%d)", size);
-  /* size_t overflow = nmemb * size; */
-  /* if (size && overflow / size != nmemb) { */
-  /*   // TODO: rsyslog() detected overflow */
-  /*   return NULL; */
-  /* } */
+  size_t overflow = nmemb * size;
+  if (size && overflow / size != nmemb) {
+    ft_printf("OVERFLOW\n");
+    // TODO: rsyslog() detected overflow
+    return NULL;
+  }
 
-  /* if (nmemb * size == 0) */
-  /*   return NULL; */
+  if (nmemb * size == 0)
+    return NULL;
 
-  lock_mutex();
   // TODO: rsyslog()
-  void *res;
-  if (nmemb * size == 0)
-    res = _malloc(1);
-  else
-    res = _malloc(nmemb * size);
+  lock_mutex();
+  void *res = _malloc(nmemb * size);
   unlock_mutex();
   ft_bzero(res, nmemb * size);
   ft_printf(" -> %p\n", res);
diff --git a/src/free.c b/src/free.c
index e52dc52..218e641 100644
--- a/src/free.c
+++ b/src/free.c
@@ -24,13 +24,12 @@ void _free(void *ptr) {
     return;
   if (!g_mmap)
     return;
-  /* t_alloc *alloc = ptr - sizeof(t_alloc); */
-  t_alloc *alloc = find_alloc_ptr(ptr);
+  t_alloc *alloc = ptr - sizeof(t_alloc);
+  /* t_alloc *alloc = find_alloc_ptr(ptr); */
   if (!alloc) {
-    ft_printf("tryed free(%p) but it's not an alloc\n", ptr);
+    ft_printf("tryed _free(%p) but it's not an alloc\n", ptr);
     return;
   }
-  ft_printf("free: (%p)->size %d\n", ptr, alloc->size);
   if (alloc->prev)
     alloc->prev->next = alloc->next;
   if (alloc->next)
@@ -54,8 +53,8 @@ void free(void *ptr) {
   ft_printf("free(%p)\n", ptr);
   if (!ptr)
     return;
-  lock_mutex();
   // TODO: rsyslog()
+  lock_mutex();
   _free(ptr);
   unlock_mutex();
 }
diff --git a/src/global_init.c b/src/global_init.c
index 7aa475c..82c2387 100644
--- a/src/global_init.c
+++ b/src/global_init.c
@@ -2,7 +2,10 @@
 
 t_mmap *g_mmap = NULL;
 
-pthread_mutex_t g_mutex = PTHREAD_MUTEX_INITIALIZER;
+pthread_mutex_t *get_mutex() {
+  static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
+  return &mutex;
+}
 
-void lock_mutex() { pthread_mutex_lock(&g_mutex); }
-void unlock_mutex() { pthread_mutex_unlock(&g_mutex); }
+void lock_mutex() { pthread_mutex_lock(get_mutex()); }
+void unlock_mutex() { pthread_mutex_unlock(get_mutex()); }
diff --git a/src/malloc.c b/src/malloc.c
index 02174bb..56f22c4 100644
--- a/src/malloc.c
+++ b/src/malloc.c
@@ -6,20 +6,19 @@ void *_malloc(size_t size) {
     return ALLOC_SHIFT(res);
   new_mmap(size);
   res = find_alloc(size);
+  if (!res)
+    ft_printf("NO SPACE FOUND ON NEW MMAP\n");
   return ALLOC_SHIFT(res);
 }
 
 void *malloc(size_t size) {
   ft_printf("malloc(%d)", size);
-  /* if (!size) */
-  /*   size = 1; */
-  if (size == 0)
+  if (!size)
     return NULL;
-  lock_mutex();
   // TODO: rsyslog()
+  lock_mutex();
   void *res = _malloc(size);
   unlock_mutex();
   ft_printf(" -> %p\n", res);
-  show_alloc_mem();
   return res;
 }
diff --git a/src/mmap.c b/src/mmap.c
index 68d1731..a9f1ea0 100644
--- a/src/mmap.c
+++ b/src/mmap.c
@@ -2,10 +2,10 @@
 
 size_t get_mmap_size(size_t size) {
   if (size <= TINY_ALLOC_SIZE)
-    return TINY_MMAP_SIZE;
+    return TINY_MMAP_SIZE + ALIGNMENT;
   if (size <= SMALL_ALLOC_SIZE)
-    return SMALL_MMAP_SIZE;
-  return size + sizeof(t_alloc);
+    return SMALL_MMAP_SIZE + ALIGNMENT;
+  return size + sizeof(t_alloc) + ALIGNMENT;
 }
 
 t_type get_mmap_type(size_t size) {
@@ -17,9 +17,8 @@ t_type get_mmap_type(size_t size) {
 }
 
 t_mmap *new_mmap(size_t size) {
-  t_mmap *map =
-      mmap(NULL, get_mmap_size(size) + sizeof(t_mmap), PROT_READ | PROT_WRITE,
-           MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+  t_mmap *map = mmap(NULL, get_mmap_size(size) + sizeof(t_mmap),
+                     PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, 0, 0);
   if (!map) {
     errno = ENOMEM;
     return NULL;
diff --git a/src/realloc.c b/src/realloc.c
index f795919..809b244 100644
--- a/src/realloc.c
+++ b/src/realloc.c
@@ -31,13 +31,14 @@ void *_realloc(void *ptr, size_t size) {
 
 void *realloc(void *ptr, size_t size) {
   ft_printf("realloc(%d) on %p", size, ptr);
-  lock_mutex();
   // TODO: rsyslog()
+  lock_mutex();
   void *res = NULL;
   if (!ptr)
     res = _malloc(size);
   else if (!size && ptr) {
     _free(ptr);
+    // TODO: should remove this is useless
     res = NULL;
   } else
     res = _realloc(ptr, size);
diff --git a/src/reallocarray.c b/src/reallocarray.c
index 8e6cca5..f069435 100644
--- a/src/reallocarray.c
+++ b/src/reallocarray.c
@@ -11,9 +11,9 @@ void *reallocarray(void *ptr, size_t nmemb, size_t size) {
   }
   if (nmemb * size == 0)
     return NULL;
-  lock_mutex();
   // TODO: rsyslog()
   void *res;
+  lock_mutex();
   if (!ptr)
     res = _malloc(size * nmemb);
   else if ((size * nmemb) == 0 && ptr) {
diff --git a/src/show_alloc_mem.c b/src/show_alloc_mem.c
index 7f71d2d..4faedf3 100644
--- a/src/show_alloc_mem.c
+++ b/src/show_alloc_mem.c
@@ -10,13 +10,16 @@ char *get_type_string(t_type type) {
 
 void show_alloc_mem() {
   if (!g_mmap) {
-    ft_putstr("No memory allocated\n");
+    ft_putstr("show_alloc_mem(): No memory allocated\n");
     return;
   }
   size_t total = 0;
   for (t_mmap *mmap = g_mmap; mmap; mmap = mmap->next) {
     ft_printf("%s : %p\n", get_type_string(mmap->type), mmap);
     for (t_alloc *alloc = mmap->alloc; alloc; alloc = alloc->next) {
+      if (!alloc) {
+        ft_printf("alloc is NULL\n");
+      }
       ft_printf("%p - %p : %d bytes\n", ALLOC_SHIFT(alloc),
                 ALLOC_SHIFT(alloc) + alloc->size, alloc->size);
       if (alloc->next == alloc) {
diff --git a/test.c b/test.c
index 0a942c1..4f8f88a 100644
--- a/test.c
+++ b/test.c
@@ -1,38 +1,48 @@
 #include "include/malloc.h"
+#include "libft/libft.h"
 #include <stdio.h>
+#include <string.h>
 #include <strings.h>
 #include <unistd.h>
 int main(void) {
-  int len = 100;
-  char *a = malloc(len);
-  ft_printf("a(%p)\n", a);
-  ft_bzero(a, len);
-  char *a1 = malloc(len);
-  ft_bzero(a1, len);
-  ft_printf("a(%p)\n", a1);
-  a = malloc(len);
-  ft_printf("a(%p)\n", a);
-  ft_bzero(a, len);
-  free(a1);
-  a = malloc(len);
-  ft_printf("a(%p)\n", a);
-  ft_bzero(a, len);
+  /* int len = 100; */
+  /* char *a = malloc(len); */
+  /* ft_printf("a(%p)\n", a); */
+  /* ft_bzero(a, len); */
+  /* char *a1 = malloc(len); */
+  /* ft_bzero(a1, len); */
+  /* ft_printf("a(%p)\n", a1); */
+  /* a = malloc(len); */
+  /* ft_printf("a(%p)\n", a); */
+  /* ft_bzero(a, len); */
+  /* free(a1); */
+  /* a = malloc(len); */
+  /* ft_printf("a(%p)\n", a); */
+  /* ft_bzero(a, len); */
+  /**/
+  /* len = 4000; */
+  /* char *b = malloc(len); */
+  /* ft_printf("b(%p)\n", b); */
+  /* ft_bzero(b, len); */
+  /**/
+  /* len = 500; */
+  /* char *c = malloc(len); */
+  /* ft_printf("c(%p)\n", c); */
+  /* ft_bzero(c, len); */
 
-  len = 4000;
-  char *b = malloc(len);
-  ft_printf("b(%p)\n", b);
-  ft_bzero(b, len);
-
-  len = 500;
-  char *c = malloc(len);
-  ft_printf("c(%p)\n", c);
-  ft_bzero(c, len);
-
-  /* ft_printf("allocating 1000 times\n"); */
-  /* for (int i = 0; i < 1000; i++) { */
-  /*   char *d = malloc(i); */
-  /*   ft_bzero(d, i); */
-  /* } */
+  ft_printf("allocating 5000 times\n");
+  for (int i = 1; i < 50000; i += 3) {
+    char *d = malloc(i);
+    /* d = realloc(d, i); */
+    /* d = realloc(d, i - 1); */
+    /* d = realloc(d, i + 1); */
+    ((void)d);
+    ft_bzero(d, i);
+    bzero(d, i);
+    ft_memset(d, 'a', i);
+    memset(d, 'b', i);
+    free(d);
+  }
 
   ft_putchar('\n');
   show_alloc_mem();
diff --git a/testreal.c b/testreal.c
new file mode 100644
index 0000000..435caa9
--- /dev/null
+++ b/testreal.c
@@ -0,0 +1,40 @@
+#include "libft/libft.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <strings.h>
+#include <unistd.h>
+int main(void) {
+  int len = 100;
+  char *a = malloc(len);
+  ft_printf("a(%p)\n", a);
+  ft_bzero(a, len);
+  char *a1 = malloc(len);
+  ft_bzero(a1, len);
+  ft_printf("a(%p)\n", a1);
+  a = malloc(len);
+  ft_printf("a(%p)\n", a);
+  ft_bzero(a, len);
+  free(a1);
+  a = malloc(len);
+  ft_printf("a(%p)\n", a);
+  ft_bzero(a, len);
+
+  len = 4000;
+  char *b = malloc(len);
+  ft_printf("b(%p)\n", b);
+  ft_bzero(b, len);
+
+  len = 500;
+  char *c = malloc(len);
+  ft_printf("c(%p)\n", c);
+  ft_bzero(c, len);
+
+  /* ft_printf("allocating 1000 times\n"); */
+  /* for (int i = 0; i < 1000; i++) { */
+  /*   char *d = malloc(i); */
+  /*   ft_bzero(d, i); */
+  /* } */
+
+  ft_putchar('\n');
+  return EXIT_SUCCESS;
+}