* 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) {
int retval = dictAdd(db->dict, copy, val);
redisAssertWithInfo(NULL,key,retval == REDIS_OK);
- if (server.cluster_enabled) SlotToKeyAdd(key);
}
/* Overwrite an existing key with a new value. Incrementing the reference
* the key, because it is shared with the main dictionary. */
if (dictSize(db->expires) > 0) dictDelete(db->expires,key->ptr);
if (dictDelete(db->dict,key->ptr) == DICT_OK) {
- if (server.cluster_enabled) SlotToKeyDel(key);
return 1;
} else {
return 0;
}
}
-/* 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;
void selectCommand(redisClient *c) {
int id = atoi(c->argv[1]->ptr);
- if (server.cluster_enabled && id != 0) {
- addReplyError(c,"SELECT is not allowed in cluster mode");
- return;
- }
if (selectDb(c,id) == REDIS_ERR) {
addReplyError(c,"invalid DB index");
} else {
redisDb *src, *dst;
int srcid;
- if (server.cluster_enabled) {
- addReplyError(c,"MOVE is not allowed in cluster mode");
- return;
- }
-
/* Obtain source and target DB pointers */
src = c->db;
srcid = c->db->id;
* 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 */
*numkeys = num;
return keys;
}
-
-/* Slot to Key API. This is used by Redis Cluster in order to obtain in
- * a fast way a key that belongs to a specified hash slot. This is useful
- * while rehashing the cluster. */
-void SlotToKeyAdd(robj *key) {
- unsigned int hashslot = keyHashSlot(key->ptr,sdslen(key->ptr));
-
- zslInsert(server.cluster.slots_to_keys,hashslot,key);
- incrRefCount(key);
-}
-
-void SlotToKeyDel(robj *key) {
- unsigned int hashslot = keyHashSlot(key->ptr,sdslen(key->ptr));
-
- zslDelete(server.cluster.slots_to_keys,hashslot,key);
-}
-
-unsigned int GetKeysInSlot(unsigned int hashslot, robj **keys, unsigned int count) {
- zskiplistNode *n;
- zrangespec range;
- int j = 0;
-
- range.min = range.max = hashslot;
- range.minex = range.maxex = 0;
-
- n = zslFirstInRange(server.cluster.slots_to_keys, range);
- while(n && n->score == hashslot && count--) {
- keys[j++] = n->obj;
- n = n->level[0].forward;
- }
- return j;
-}