diff --git a/src/object.c b/src/object.c
index 87b32f42..48ffa42b 100644
--- a/src/object.c
+++ b/src/object.c
@@ -1285,8 +1285,6 @@ NULL
  *
  * Usage: MEMORY usage <key> */
 void memoryCommand(client *c) {
-    robj *o;
-
     if (!strcasecmp(c->argv[1]->ptr,"help") && c->argc == 2) {
         const char *help[] = {
 "DOCTOR - Return memory problems reports.",
@@ -1298,6 +1296,7 @@ NULL
         };
         addReplyHelp(c, help);
     } else if (!strcasecmp(c->argv[1]->ptr,"usage") && c->argc >= 3) {
+        dictEntry *de;
         long long samples = OBJ_COMPUTE_SIZE_DEF_SAMPLES;
         for (int j = 3; j < c->argc; j++) {
             if (!strcasecmp(c->argv[j]->ptr,"samples") &&
@@ -1316,10 +1315,12 @@ NULL
                 return;
             }
         }
-        if ((o = objectCommandLookupOrReply(c,c->argv[2],shared.nullbulk))
-                == NULL) return;
-        size_t usage = objectComputeSize(o,samples);
-        usage += sdsAllocSize(c->argv[2]->ptr);
+        if ((de = dictFind(c->db->dict,c->argv[2]->ptr)) == NULL) {
+            addReply(c, shared.nullbulk);
+            return;
+        }
+        size_t usage = objectComputeSize(dictGetVal(de),samples);
+        usage += sdsAllocSize(dictGetKey(de));
         usage += sizeof(dictEntry);
         addReplyLongLong(c,usage);
     } else if (!strcasecmp(c->argv[1]->ptr,"stats") && c->argc == 2) {