remove mentions of VM in comments

[redis.git] / src / db.c

diff --git a/src/db.c b/src/db.c
index 3ff7113b7447159501818b8a2bb11e63a47beb3a..492e7aba2c4f7f5d727badefe352c76e744dc681 100644 (file)
--- a/src/db.c
+++ b/src/db.c
@@ -10,28 +10,6 @@ void SlotToKeyDel(robj *key);
  * C-level DB API
  *----------------------------------------------------------------------------*/
 
-/* Important notes on lookup and disk store.
- *
- * When disk store is enabled on lookup we can have different cases.
- *
- * a) The key is in memory:
- *    - If the key is not in IO_SAVEINPROG state we can access it.
- *      As if it's just IO_SAVE this means we have the key in the IO queue
- *      but can't be accessed by the IO thread (it requires to be
- *      translated into an IO Job by the cache cron function.)
- *    - If the key is in IO_SAVEINPROG we can't touch the key and have
- *      to blocking wait completion of operations.
- * b) The key is not in memory:
- *    - If it's marked as non existing on disk as well (negative cache)
- *      we don't need to perform the disk access.
- *    - if the key MAY EXIST, but is not in memory, and it is marked as IO_SAVE
- *      then the key can only be a deleted one. As IO_SAVE keys are never
- *      evicted (dirty state), so the only possibility is that key was deleted.
- *    - if the key MAY EXIST we need to blocking load it.
- *      We check that the key is not in IO_SAVEINPROG state before accessing
- *      the disk object. If it is in this state, we wait.
- */
-
 robj *lookupKey(redisDb *db, robj *key) {
     dictEntry *de = dictFind(db->dict,key->ptr);
     if (de) {
@@ -42,17 +20,22 @@ robj *lookupKey(redisDb *db, robj *key) {
          * a copy on write madness. */
         if (server.rdb_child_pid == -1 && server.aof_child_pid == -1)
             val->lru = server.lruclock;
-        server.stat_keyspace_hits++;
         return val;
     } else {
-        server.stat_keyspace_misses++;
         return NULL;
     }
 }
 
 robj *lookupKeyRead(redisDb *db, robj *key) {
+    robj *val;
+
     expireIfNeeded(db,key);
-    return lookupKey(db,key);
+    val = lookupKey(db,key);
+    if (val == NULL)
+        server.stat_keyspace_misses++;
+    else
+        server.stat_keyspace_hits++;
+    return val;
 }
 
 robj *lookupKeyWrite(redisDb *db, robj *key) {
@@ -156,8 +139,6 @@ int dbDelete(redisDb *db, robj *key) {
     }
 }
 
-/* Empty the whole database.
- * If diskstore is enabled this function will just flush the in-memory cache. */
 long long emptyDb() {
     int j;
     long long removed = 0;
@@ -483,9 +464,10 @@ long long getExpire(redisDb *db, robj *key) {
 void propagateExpire(redisDb *db, robj *key) {
     robj *argv[2];
 
-    argv[0] = createStringObject("DEL",3);
+    argv[0] = shared.del;
     argv[1] = key;
-    incrRefCount(key);
+    incrRefCount(argv[0]);
+    incrRefCount(argv[1]);
 
     if (server.aof_state != REDIS_AOF_OFF)
         feedAppendOnlyFile(server.delCommand,db->id,argv,2);
@@ -512,7 +494,7 @@ int expireIfNeeded(redisDb *db, robj *key) {
      * that is, 0 if we think the key should be still valid, 1 if
      * we think the key is expired at this time. */
     if (server.masterhost != NULL) {
-        return time(NULL) > when;
+        return mstime() > when;
     }
 
     /* Return when this key has not expired */