support for write operations against expiring keys, by master-controlled expiring in replication and AOF synthesizing DEL operations

This commit is contained in:
antirez
2010-08-02 18:13:39 +02:00
parent 0c7a9dec65
commit bcf2995c98
4 changed files with 86 additions and 49 deletions

View File

@ -435,6 +435,48 @@ void updateDictResizePolicy(void) {
/* ======================= Cron: called every 100 ms ======================== */
/* Try to expire a few timed out keys. The algorithm used is adaptive and
* will use few CPU cycles if there are few expiring keys, otherwise
* it will get more aggressive to avoid that too much memory is used by
* keys that can be removed from the keyspace. */
void activeExpireCycle(void) {
int j;
for (j = 0; j < server.dbnum; j++) {
int expired;
redisDb *db = server.db+j;
/* Continue to expire if at the end of the cycle more than 25%
* of the keys were expired. */
do {
long num = dictSize(db->expires);
time_t now = time(NULL);
expired = 0;
if (num > REDIS_EXPIRELOOKUPS_PER_CRON)
num = REDIS_EXPIRELOOKUPS_PER_CRON;
while (num--) {
dictEntry *de;
time_t t;
if ((de = dictGetRandomKey(db->expires)) == NULL) break;
t = (time_t) dictGetEntryVal(de);
if (now > t) {
sds key = dictGetEntryKey(de);
robj *keyobj = createStringObject(key,sdslen(key));
propagateExpire(db,keyobj);
dbDelete(db,keyobj);
decrRefCount(keyobj);
expired++;
server.stat_expiredkeys++;
}
}
} while (expired > REDIS_EXPIRELOOKUPS_PER_CRON/4);
}
}
int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientData) {
int j, loops = server.cronloops++;
REDIS_NOTUSED(eventLoop);
@ -533,41 +575,10 @@ int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientData) {
}
}
/* Try to expire a few timed out keys. The algorithm used is adaptive and
* will use few CPU cycles if there are few expiring keys, otherwise
* it will get more aggressive to avoid that too much memory is used by
* keys that can be removed from the keyspace. */
for (j = 0; j < server.dbnum; j++) {
int expired;
redisDb *db = server.db+j;
/* Continue to expire if at the end of the cycle more than 25%
* of the keys were expired. */
do {
long num = dictSize(db->expires);
time_t now = time(NULL);
expired = 0;
if (num > REDIS_EXPIRELOOKUPS_PER_CRON)
num = REDIS_EXPIRELOOKUPS_PER_CRON;
while (num--) {
dictEntry *de;
time_t t;
if ((de = dictGetRandomKey(db->expires)) == NULL) break;
t = (time_t) dictGetEntryVal(de);
if (now > t) {
sds key = dictGetEntryKey(de);
robj *keyobj = createStringObject(key,sdslen(key));
dbDelete(db,keyobj);
decrRefCount(keyobj);
expired++;
server.stat_expiredkeys++;
}
}
} while (expired > REDIS_EXPIRELOOKUPS_PER_CRON/4);
}
/* Expire a few keys per cycle, only if this is a master.
* On slaves we wait for DEL operations synthesized by the master
* in order to guarantee a strict consistency. */
if (server.masterhost == NULL) activeExpireCycle();
/* Swap a few keys on disk if we are over the memory limit and VM
* is enbled. Try to free objects from the free list first. */