diff --git a/pinos/client/array.h b/pinos/client/array.h
index 96b8f5177..a4fa62b9e 100644
--- a/pinos/client/array.h
+++ b/pinos/client/array.h
@@ -32,8 +32,11 @@ struct _PinosArray {
   void    *data;
   size_t   size;
   size_t   alloc;
+  size_t   extend;
 };
 
+#define PINOS_ARRAY_INIT(extend) { NULL, 0, 0, extend }
+
 #define pinos_array_get_len_s(a,s)              ((a)->size / (s))
 #define pinos_array_get_unchecked_s(a,idx,s,t)  SPA_MEMBER ((a)->data,(idx)*(s),t)
 #define pinos_array_check_index_s(a,idx,s)      ((idx) < pinos_array_get_len(a,s))
@@ -48,10 +51,11 @@ struct _PinosArray {
          (pos)++)
 
 static inline void
-pinos_array_init (PinosArray *arr)
+pinos_array_init (PinosArray *arr, size_t extend)
 {
   arr->data = NULL;
   arr->size = arr->alloc = 0;
+  arr->extend = extend;
 }
 
 static inline void
@@ -71,7 +75,7 @@ pinos_array_ensure_size (PinosArray *arr,
 
   if (SPA_UNLIKELY (alloc < need)) {
     void *data;
-    alloc = SPA_MAX (alloc, 16);
+    alloc = SPA_MAX (alloc, arr->extend);
     while (alloc < need)
       alloc *= 2;
     if (SPA_UNLIKELY ((data = realloc (arr->data, alloc)) == NULL))
diff --git a/pinos/client/connection.c b/pinos/client/connection.c
index 4eb3f01dc..0fb34564b 100644
--- a/pinos/client/connection.c
+++ b/pinos/client/connection.c
@@ -277,7 +277,7 @@ again:
   *dt = buf->data;
   *sz = buf->size;
 
-  spa_debug_pod (data);
+//  spa_debug_pod (data);
 
   return true;
 }
@@ -310,7 +310,7 @@ pinos_connection_end_write (PinosConnection  *conn,
 
   buf->buffer_size += 8 + size;
 
-  spa_debug_pod (p);
+//  spa_debug_pod (p);
 
   pinos_signal_emit (&conn->need_flush, conn);
 }
diff --git a/pinos/client/context.c b/pinos/client/context.c
index f0fcffe99..4de993edc 100644
--- a/pinos/client/context.c
+++ b/pinos/client/context.c
@@ -486,8 +486,8 @@ pinos_context_new (PinosLoop       *loop,
 
   this->state = PINOS_CONTEXT_STATE_UNCONNECTED;
 
-  pinos_map_init (&this->objects, 64);
-  pinos_map_init (&this->uris, 64);
+  pinos_map_init (&this->objects, 64, 32);
+  pinos_map_init (&this->uris, 64, 32);
 
   spa_list_init (&this->stream_list);
   spa_list_init (&this->global_list);
diff --git a/pinos/client/map.h b/pinos/client/map.h
index aff00d82a..8913ddf67 100644
--- a/pinos/client/map.h
+++ b/pinos/client/map.h
@@ -43,6 +43,8 @@ struct _PinosMap {
   uint32_t   free_list;
 };
 
+#define PINOS_MAP_INIT(extend) { PINOS_ARRAY_INIT(extend), 0 }
+
 #define pinos_map_get_size(m)            pinos_array_get_len (&(m)->items, PinosMapItem)
 #define pinos_map_get_item(m,id)         pinos_array_get_unchecked(&(m)->items,id,PinosMapItem)
 #define pinos_map_item_is_free(item)     ((item)->next & 0x1)
@@ -53,9 +55,10 @@ struct _PinosMap {
 
 static inline void
 pinos_map_init (PinosMap *map,
-                size_t    size)
+                size_t    size,
+                size_t    extend)
 {
-  pinos_array_init (&map->items);
+  pinos_array_init (&map->items, extend);
   pinos_array_ensure_size (&map->items, size * sizeof (PinosMapItem));
   map->free_list = 0;
 }
diff --git a/pinos/client/mapper.c b/pinos/client/mapper.c
index 96de7e89f..c9c29289f 100644
--- a/pinos/client/mapper.c
+++ b/pinos/client/mapper.c
@@ -27,25 +27,31 @@
 
 #include <pinos/client/map.h>
 
-#define MAX_URIS 4096
-
 typedef struct {
   SpaIDMap map;
   PinosMap uris;
+  PinosArray strings;
 } IDMap;
 
 static uint32_t
 id_map_get_id (SpaIDMap *map, const char *uri)
 {
   IDMap *this = SPA_CONTAINER_OF (map, IDMap, map);
-  uint32_t i = 0;
+  uint32_t i = 0, len;
+  void *p;
+  off_t o;
 
   if (uri != NULL) {
     for (i = 0; i < pinos_map_get_size (&this->uris); i++) {
-      if (strcmp (pinos_map_lookup_unchecked (&this->uris, i), uri) == 0)
+      o = (off_t) pinos_map_lookup_unchecked (&this->uris, i);
+      if (strcmp (SPA_MEMBER (this->strings.data, o, char), uri) == 0)
         return i;
     }
-    i = pinos_map_insert_new (&this->uris, strdup (uri));
+    len = strlen (uri);
+    p = pinos_array_add (&this->strings, SPA_ROUND_UP_N (len+1, 2));
+    memcpy (p, uri, len+1);
+    o = (p - this->strings.data);
+    i = pinos_map_insert_new (&this->uris, (void *)o);
   }
   return i;
 }
@@ -54,12 +60,14 @@ static const char *
 id_map_get_uri (SpaIDMap *map, uint32_t id)
 {
   IDMap *this = SPA_CONTAINER_OF (map, IDMap, map);
+
   if (id == SPA_ID_INVALID)
     return NULL;
 
-  if (SPA_LIKELY (pinos_map_check_id (&this->uris, id)))
-    return pinos_map_lookup_unchecked (&this->uris, id);
-
+  if (SPA_LIKELY (pinos_map_check_id (&this->uris, id))) {
+    off_t o = (off_t) pinos_map_lookup_unchecked (&this->uris, id);
+    return SPA_MEMBER (this->strings.data, o, char);
+  }
   return NULL;
 }
 
@@ -77,7 +85,8 @@ static IDMap default_id_map = {
     id_map_get_uri,
     id_map_get_size,
   },
-  { { NULL, } },
+  PINOS_MAP_INIT(128),
+  PINOS_ARRAY_INIT (4096)
 };
 
 SpaIDMap *
diff --git a/pinos/client/properties.c b/pinos/client/properties.c
index 668d1f02a..e33e04a6d 100644
--- a/pinos/client/properties.c
+++ b/pinos/client/properties.c
@@ -81,7 +81,7 @@ pinos_properties_new (const char *key, ...)
   if (impl == NULL)
     return NULL;
 
-  pinos_array_init (&impl->items);
+  pinos_array_init (&impl->items, 16);
 
   va_start (varargs, key);
   while (key != NULL) {
@@ -112,7 +112,7 @@ pinos_properties_new_dict (const SpaDict *dict)
   if (impl == NULL)
     return NULL;
 
-  pinos_array_init (&impl->items);
+  pinos_array_init (&impl->items, 16);
 
   for (i = 0; i < dict->n_items; i++)
     add_func (&impl->this, strdup (dict->items[i].key), strdup (dict->items[i].value));
diff --git a/pinos/client/stream.c b/pinos/client/stream.c
index 1fe7f72bd..57fe249c5 100644
--- a/pinos/client/stream.c
+++ b/pinos/client/stream.c
@@ -225,9 +225,9 @@ pinos_stream_new (PinosContext    *context,
   this->state = PINOS_STREAM_STATE_UNCONNECTED;
 
   impl->node_state = SPA_NODE_STATE_INIT;
-  pinos_array_init (&impl->mem_ids);
+  pinos_array_init (&impl->mem_ids, 64);
   pinos_array_ensure_size (&impl->mem_ids, sizeof (MemId) * 64);
-  pinos_array_init (&impl->buffer_ids);
+  pinos_array_init (&impl->buffer_ids, 32);
   pinos_array_ensure_size (&impl->buffer_ids, sizeof (BufferId) * 64);
   impl->pending_seq = SPA_ID_INVALID;
 
diff --git a/pinos/client/utils.c b/pinos/client/utils.c
index 2824dd9a8..ec2e38720 100644
--- a/pinos/client/utils.c
+++ b/pinos/client/utils.c
@@ -53,7 +53,7 @@ pinos_split_strv (const char *str,
   size_t len;
   int n = 0;
 
-  pinos_array_init (&arr);
+  pinos_array_init (&arr, 16);
 
   s = pinos_split_walk (str, delimiter, &len, &state);
   while (s && n + 1 < max_tokens) {
diff --git a/pinos/server/client.c b/pinos/server/client.c
index 57cc3f421..d649e5fde 100644
--- a/pinos/server/client.c
+++ b/pinos/server/client.c
@@ -105,8 +105,8 @@ pinos_client_new (PinosCore       *core,
   pinos_signal_init (&this->resource_added);
   pinos_signal_init (&this->resource_removed);
 
-  pinos_map_init (&this->objects, 0);
-  pinos_map_init (&this->uris, 0);
+  pinos_map_init (&this->objects, 0, 32);
+  pinos_map_init (&this->uris, 0, 32);
   pinos_signal_init (&this->destroy_signal);
 
   spa_list_insert (core->client_list.prev, &this->link);
diff --git a/pinos/server/core.c b/pinos/server/core.c
index 7057f45d6..67ab8ef27 100644
--- a/pinos/server/core.c
+++ b/pinos/server/core.c
@@ -293,7 +293,7 @@ pinos_core_new (PinosMainLoop   *main_loop,
 
   pinos_uri_init (&this->uri);
   pinos_access_init (&this->access);
-  pinos_map_init (&this->objects, 512);
+  pinos_map_init (&this->objects, 128, 32);
 
   impl->support[0].uri = SPA_ID_MAP_URI;
   impl->support[0].data = this->uri.map;