static void setProtocolError(redisClient *c, int pos);
+/* To evaluate the output buffer size of a client we need to get size of
+ * allocated objects, however we can't used zmalloc_size() directly on sds
+ * strings because of the trick they use to work (the header is before the
+ * returned pointer), so we use this helper function. */
+size_t zmalloc_size_sds(sds s) {
+ return zmalloc_size(s-sizeof(struct sdshdr));
+}
+
void *dupClientReplyValue(void *o) {
incrRefCount((robj*)o);
return o;
c->replstate = REDIS_REPL_NONE;
c->reply = listCreate();
c->reply_bytes = 0;
+ c->obuf_soft_limit_reached_time = 0;
listSetFreeMethod(c->reply,decrRefCount);
listSetDupMethod(c->reply,dupClientReplyValue);
c->bpop.keys = NULL;
return c;
}
-/* Set the event loop to listen for write events on the client's socket.
- * Typically gets called every time a reply is built. */
-int _installWriteEvent(redisClient *c) {
+/* This function is called every time we are going to transmit new data
+ * to the client. The behavior is the following:
+ *
+ * If the client should receive new data (normal clients will) the function
+ * returns REDIS_OK, and make sure to install the write handler in our event
+ * loop so that when the socket is writable new data gets written.
+ *
+ * If the client should not receive new data, because it is a fake client
+ * or a slave, or because the setup of the write handler failed, the function
+ * returns REDIS_ERR.
+ *
+ * Typically gets called every time a reply is built, before adding more
+ * data to the clients output buffers. If the function returns REDIS_ERR no
+ * data should be appended to the output buffers. */
+int prepareClientToWrite(redisClient *c) {
if (c->flags & REDIS_LUA_CLIENT) return REDIS_OK;
- if (c->fd <= 0) return REDIS_ERR;
+ if (c->fd <= 0) return REDIS_ERR; /* Fake client */
if (c->bufpos == 0 && listLength(c->reply) == 0 &&
(c->replstate == REDIS_REPL_NONE ||
c->replstate == REDIS_REPL_ONLINE) &&
if (listLength(c->reply) == 0) {
incrRefCount(o);
listAddNodeTail(c->reply,o);
+ c->reply_bytes += zmalloc_size_sds(o->ptr);
} else {
tail = listNodeValue(listLast(c->reply));
if (tail->ptr != NULL &&
sdslen(tail->ptr)+sdslen(o->ptr) <= REDIS_REPLY_CHUNK_BYTES)
{
+ c->reply_bytes -= zmalloc_size_sds(tail->ptr);
tail = dupLastObjectIfNeeded(c->reply);
tail->ptr = sdscatlen(tail->ptr,o->ptr,sdslen(o->ptr));
+ c->reply_bytes += zmalloc_size_sds(tail->ptr);
} else {
incrRefCount(o);
listAddNodeTail(c->reply,o);
+ c->reply_bytes += zmalloc_size_sds(o->ptr);
}
}
- c->reply_bytes += sdslen(o->ptr);
+ asyncCloseClientOnOutputBufferLimitReached(c);
}
/* This method takes responsibility over the sds. When it is no longer
return;
}
- c->reply_bytes += sdslen(s);
if (listLength(c->reply) == 0) {
listAddNodeTail(c->reply,createObject(REDIS_STRING,s));
+ c->reply_bytes += zmalloc_size_sds(s);
} else {
tail = listNodeValue(listLast(c->reply));
if (tail->ptr != NULL &&
sdslen(tail->ptr)+sdslen(s) <= REDIS_REPLY_CHUNK_BYTES)
{
+ c->reply_bytes -= zmalloc_size_sds(tail->ptr);
tail = dupLastObjectIfNeeded(c->reply);
tail->ptr = sdscatlen(tail->ptr,s,sdslen(s));
+ c->reply_bytes += zmalloc_size_sds(tail->ptr);
sdsfree(s);
} else {
listAddNodeTail(c->reply,createObject(REDIS_STRING,s));
+ c->reply_bytes += zmalloc_size_sds(s);
}
}
+ asyncCloseClientOnOutputBufferLimitReached(c);
}
void _addReplyStringToList(redisClient *c, char *s, size_t len) {
if (c->flags & REDIS_CLOSE_AFTER_REPLY) return;
if (listLength(c->reply) == 0) {
- listAddNodeTail(c->reply,createStringObject(s,len));
+ robj *o = createStringObject(s,len);
+
+ listAddNodeTail(c->reply,o);
+ c->reply_bytes += zmalloc_size_sds(o->ptr);
} else {
tail = listNodeValue(listLast(c->reply));
if (tail->ptr != NULL &&
sdslen(tail->ptr)+len <= REDIS_REPLY_CHUNK_BYTES)
{
+ c->reply_bytes -= zmalloc_size_sds(tail->ptr);
tail = dupLastObjectIfNeeded(c->reply);
tail->ptr = sdscatlen(tail->ptr,s,len);
+ c->reply_bytes += zmalloc_size_sds(tail->ptr);
} else {
- listAddNodeTail(c->reply,createStringObject(s,len));
+ robj *o = createStringObject(s,len);
+
+ listAddNodeTail(c->reply,o);
+ c->reply_bytes += zmalloc_size_sds(o->ptr);
}
}
- c->reply_bytes += len;
+ asyncCloseClientOnOutputBufferLimitReached(c);
}
/* -----------------------------------------------------------------------------
* -------------------------------------------------------------------------- */
void addReply(redisClient *c, robj *obj) {
- if (_installWriteEvent(c) != REDIS_OK) return;
+ if (prepareClientToWrite(c) != REDIS_OK) return;
/* This is an important place where we can avoid copy-on-write
* when there is a saving child running, avoiding touching the
if (obj->encoding == REDIS_ENCODING_RAW) {
if (_addReplyToBuffer(c,obj->ptr,sdslen(obj->ptr)) != REDIS_OK)
_addReplyObjectToList(c,obj);
- } else {
- /* FIXME: convert the long into string and use _addReplyToBuffer()
- * instead of calling getDecodedObject. As this place in the
- * code is too performance critical. */
+ } else if (obj->encoding == REDIS_ENCODING_INT) {
+ /* Optimization: if there is room in the static buffer for 32 bytes
+ * (more than the max chars a 64 bit integer can take as string) we
+ * avoid decoding the object and go for the lower level approach. */
+ if (listLength(c->reply) == 0 && (sizeof(c->buf) - c->bufpos) >= 32) {
+ char buf[32];
+ int len;
+
+ len = ll2string(buf,sizeof(buf),(long)obj->ptr);
+ if (_addReplyToBuffer(c,buf,len) == REDIS_OK)
+ return;
+ /* else... continue with the normal code path, but should never
+ * happen actually since we verified there is room. */
+ }
obj = getDecodedObject(obj);
if (_addReplyToBuffer(c,obj->ptr,sdslen(obj->ptr)) != REDIS_OK)
_addReplyObjectToList(c,obj);
decrRefCount(obj);
+ } else {
+ redisPanic("Wrong obj->encoding in addReply()");
}
}
void addReplySds(redisClient *c, sds s) {
- if (_installWriteEvent(c) != REDIS_OK) {
+ if (prepareClientToWrite(c) != REDIS_OK) {
/* The caller expects the sds to be free'd. */
sdsfree(s);
return;
}
void addReplyString(redisClient *c, char *s, size_t len) {
- if (_installWriteEvent(c) != REDIS_OK) return;
+ if (prepareClientToWrite(c) != REDIS_OK) return;
if (_addReplyToBuffer(c,s,len) != REDIS_OK)
_addReplyStringToList(c,s,len);
}
-void _addReplyError(redisClient *c, char *s, size_t len) {
+void addReplyErrorLength(redisClient *c, char *s, size_t len) {
addReplyString(c,"-ERR ",5);
addReplyString(c,s,len);
addReplyString(c,"\r\n",2);
}
void addReplyError(redisClient *c, char *err) {
- _addReplyError(c,err,strlen(err));
+ addReplyErrorLength(c,err,strlen(err));
}
void addReplyErrorFormat(redisClient *c, const char *fmt, ...) {
for (j = 0; j < l; j++) {
if (s[j] == '\r' || s[j] == '\n') s[j] = ' ';
}
- _addReplyError(c,s,sdslen(s));
+ addReplyErrorLength(c,s,sdslen(s));
sdsfree(s);
}
-void _addReplyStatus(redisClient *c, char *s, size_t len) {
+void addReplyStatusLength(redisClient *c, char *s, size_t len) {
addReplyString(c,"+",1);
addReplyString(c,s,len);
addReplyString(c,"\r\n",2);
}
void addReplyStatus(redisClient *c, char *status) {
- _addReplyStatus(c,status,strlen(status));
+ addReplyStatusLength(c,status,strlen(status));
}
void addReplyStatusFormat(redisClient *c, const char *fmt, ...) {
va_start(ap,fmt);
sds s = sdscatvprintf(sdsempty(),fmt,ap);
va_end(ap);
- _addReplyStatus(c,s,sdslen(s));
+ addReplyStatusLength(c,s,sdslen(s));
sdsfree(s);
}
/* Note that we install the write event here even if the object is not
* ready to be sent, since we are sure that before returning to the
* event loop setDeferredMultiBulkLength() will be called. */
- if (_installWriteEvent(c) != REDIS_OK) return NULL;
+ if (prepareClientToWrite(c) != REDIS_OK) return NULL;
listAddNodeTail(c->reply,createObject(REDIS_STRING,NULL));
return listLast(c->reply);
}
len = listNodeValue(ln);
len->ptr = sdscatprintf(sdsempty(),"*%ld\r\n",length);
- c->reply_bytes += sdslen(len->ptr);
+ c->reply_bytes += zmalloc_size_sds(len->ptr);
if (ln->next != NULL) {
next = listNodeValue(ln->next);
listDelNode(c->reply,ln->next);
}
}
+ asyncCloseClientOnOutputBufferLimitReached(c);
}
/* Add a duble as a bulk reply */
/* Add a long long as integer reply or bulk len / multi bulk count.
* Basically this is used to output <prefix><long long><crlf>. */
-void _addReplyLongLong(redisClient *c, long long ll, char prefix) {
+void addReplyLongLongWithPrefix(redisClient *c, long long ll, char prefix) {
char buf[128];
int len;
+
+ /* Things like $3\r\n or *2\r\n are emitted very often by the protocol
+ * so we have a few shared objects to use if the integer is small
+ * like it is most of the times. */
+ if (prefix == '*' && ll < REDIS_SHARED_BULKHDR_LEN) {
+ addReply(c,shared.mbulkhdr[ll]);
+ return;
+ } else if (prefix == '$' && ll < REDIS_SHARED_BULKHDR_LEN) {
+ addReply(c,shared.bulkhdr[ll]);
+ return;
+ }
+
buf[0] = prefix;
len = ll2string(buf+1,sizeof(buf)-1,ll);
buf[len+1] = '\r';
else if (ll == 1)
addReply(c,shared.cone);
else
- _addReplyLongLong(c,ll,':');
+ addReplyLongLongWithPrefix(c,ll,':');
}
void addReplyMultiBulkLen(redisClient *c, long length) {
- _addReplyLongLong(c,length,'*');
+ addReplyLongLongWithPrefix(c,length,'*');
}
/* Create the length prefix of a bulk reply, example: $2234 */
len++;
}
}
- _addReplyLongLong(c,len,'$');
+ addReplyLongLongWithPrefix(c,len,'$');
}
/* Add a Redis Object as a bulk reply */
/* Add a C buffer as bulk reply */
void addReplyBulkCBuffer(redisClient *c, void *p, size_t len) {
- _addReplyLongLong(c,len,'$');
+ addReplyLongLongWithPrefix(c,len,'$');
addReplyString(c,p,len);
addReply(c,shared.crlf);
}
}
}
}
+
+ /* If this client was scheduled for async freeing we need to remove it
+ * from the queue. */
+ if (c->flags & REDIS_CLOSE_ASAP) {
+ ln = listSearchKey(server.clients_to_close,c);
+ redisAssert(ln != NULL);
+ listDelNode(server.clients_to_close,ln);
+ }
+
/* Release memory */
zfree(c->argv);
freeClientMultiState(c);
zfree(c);
}
+/* Schedule a client to free it at a safe time in the serverCron() function.
+ * This function is useful when we need to terminate a client but we are in
+ * a context where calling freeClient() is not possible, because the client
+ * should be valid for the continuation of the flow of the program. */
+void freeClientAsync(redisClient *c) {
+ if (c->flags & REDIS_CLOSE_ASAP) return;
+ c->flags |= REDIS_CLOSE_ASAP;
+ listAddNodeTail(server.clients_to_close,c);
+}
+
+void freeClientsInAsyncFreeQueue(void) {
+ while (listLength(server.clients_to_close)) {
+ listNode *ln = listFirst(server.clients_to_close);
+ redisClient *c = listNodeValue(ln);
+
+ c->flags &= ~REDIS_CLOSE_ASAP;
+ freeClient(c);
+ listDelNode(server.clients_to_close,ln);
+ }
+}
+
void sendReplyToClient(aeEventLoop *el, int fd, void *privdata, int mask) {
redisClient *c = privdata;
int nwritten = 0, totwritten = 0, objlen;
+ size_t objmem;
robj *o;
REDIS_NOTUSED(el);
REDIS_NOTUSED(mask);
} else {
o = listNodeValue(listFirst(c->reply));
objlen = sdslen(o->ptr);
+ objmem = zmalloc_size_sds(o->ptr);
if (objlen == 0) {
listDelNode(c->reply,listFirst(c->reply));
if (c->sentlen == objlen) {
listDelNode(c->reply,listFirst(c->reply));
c->sentlen = 0;
- c->reply_bytes -= objlen;
+ c->reply_bytes -= objmem;
}
}
- /* Note that we avoid to send more thank REDIS_MAX_WRITE_PER_EVENT
+ /* Note that we avoid to send more than REDIS_MAX_WRITE_PER_EVENT
* bytes, in a single threaded server it's a good idea to serve
* other clients as well, even if a very large request comes from
* super fast link that is always able to accept data (in real world
- * scenario think about 'KEYS *' against the loopback interfae) */
- if (totwritten > REDIS_MAX_WRITE_PER_EVENT) break;
+ * scenario think about 'KEYS *' against the loopback interface).
+ *
+ * However if we are over the maxmemory limit we ignore that and
+ * just deliver as much data as it is possible to deliver. */
+ if (totwritten > REDIS_MAX_WRITE_PER_EVENT &&
+ (server.maxmemory == 0 ||
+ zmalloc_used_memory() < server.maxmemory)) break;
}
if (nwritten == -1) {
if (errno == EAGAIN) {
if (client->flags & REDIS_DIRTY_CAS) *p++ = 'd';
if (client->flags & REDIS_CLOSE_AFTER_REPLY) *p++ = 'c';
if (client->flags & REDIS_UNBLOCKED) *p++ = 'u';
+ if (client->flags & REDIS_CLOSE_ASAP) *p++ = 'A';
if (p == flags) *p++ = 'N';
*p++ = '\0';
*
* Note: this function is very fast so can be called as many time as
* the caller wishes. The main usage of this function currently is
- * enforcing the client output lenght limits. */
+ * enforcing the client output length limits. */
unsigned long getClientOutputBufferMemoryUsage(redisClient *c) {
- unsigned long list_item_size = sizeof(listNode);
+ unsigned long list_item_size = sizeof(listNode)+sizeof(robj);
return c->reply_bytes + (list_item_size*listLength(c->reply));
}
+
+/* Get the class of a client, used in order to envorce limits to different
+ * classes of clients.
+ *
+ * The function will return one of the following:
+ * REDIS_CLIENT_LIMIT_CLASS_NORMAL -> Normal client
+ * REDIS_CLIENT_LIMIT_CLASS_SLAVE -> Slave or client executing MONITOR command
+ * REDIS_CLIENT_LIMIT_CLASS_PUBSUB -> Client subscribed to Pub/Sub channels
+ */
+int getClientLimitClass(redisClient *c) {
+ if (c->flags & REDIS_SLAVE) return REDIS_CLIENT_LIMIT_CLASS_SLAVE;
+ if (dictSize(c->pubsub_channels) || listLength(c->pubsub_patterns))
+ return REDIS_CLIENT_LIMIT_CLASS_PUBSUB;
+ return REDIS_CLIENT_LIMIT_CLASS_NORMAL;
+}
+
+int getClientLimitClassByName(char *name) {
+ if (!strcasecmp(name,"normal")) return REDIS_CLIENT_LIMIT_CLASS_NORMAL;
+ else if (!strcasecmp(name,"slave")) return REDIS_CLIENT_LIMIT_CLASS_SLAVE;
+ else if (!strcasecmp(name,"pubsub")) return REDIS_CLIENT_LIMIT_CLASS_PUBSUB;
+ else return -1;
+}
+
+char *getClientLimitClassName(int class) {
+ switch(class) {
+ case REDIS_CLIENT_LIMIT_CLASS_NORMAL: return "normal";
+ case REDIS_CLIENT_LIMIT_CLASS_SLAVE: return "slave";
+ case REDIS_CLIENT_LIMIT_CLASS_PUBSUB: return "pubsub";
+ default: return NULL;
+ }
+}
+
+/* The function checks if the client reached output buffer soft or hard
+ * limit, and also update the state needed to check the soft limit as
+ * a side effect.
+ *
+ * Return value: non-zero if the client reached the soft or the hard limit.
+ * Otherwise zero is returned. */
+int checkClientOutputBufferLimits(redisClient *c) {
+ int soft = 0, hard = 0, class;
+ unsigned long used_mem = getClientOutputBufferMemoryUsage(c);
+
+ class = getClientLimitClass(c);
+ if (server.client_obuf_limits[class].hard_limit_bytes &&
+ used_mem >= server.client_obuf_limits[class].hard_limit_bytes)
+ hard = 1;
+ if (server.client_obuf_limits[class].soft_limit_bytes &&
+ used_mem >= server.client_obuf_limits[class].soft_limit_bytes)
+ soft = 1;
+
+ /* We need to check if the soft limit is reached continuously for the
+ * specified amount of seconds. */
+ if (soft) {
+ if (c->obuf_soft_limit_reached_time == 0) {
+ c->obuf_soft_limit_reached_time = server.unixtime;
+ soft = 0; /* First time we see the soft limit reached */
+ } else {
+ time_t elapsed = server.unixtime - c->obuf_soft_limit_reached_time;
+
+ if (elapsed <=
+ server.client_obuf_limits[class].soft_limit_seconds) {
+ soft = 0; /* The client still did not reached the max number of
+ seconds for the soft limit to be considered
+ reached. */
+ }
+ }
+ } else {
+ c->obuf_soft_limit_reached_time = 0;
+ }
+ return soft || hard;
+}
+
+/* Asynchronously close a client if soft or hard limit is reached on the
+ * output buffer size. The caller can check if the client will be closed
+ * checking if the client REDIS_CLOSE_ASAP flag is set.
+ *
+ * Note: we need to close the client asynchronously because this function is
+ * called from contexts where the client can't be freed safely, i.e. from the
+ * lower level functions pushing data inside the client output buffers. */
+void asyncCloseClientOnOutputBufferLimitReached(redisClient *c) {
+ if (c->flags & REDIS_CLOSE_ASAP) return;
+ if (checkClientOutputBufferLimits(c)) {
+ sds client = getClientInfoString(c);
+
+ freeClientAsync(c);
+ redisLog(REDIS_WARNING,"Client %s scheduled to be closed ASAP for overcoming of output buffer limits.", client);
+ sdsfree(client);
+ }
+}
+
+/* Helper function used by freeMemoryIfNeeded() in order to flush slaves
+ * output buffers without returning control to the event loop. */
+void flushSlavesOutputBuffers(void) {
+ listIter li;
+ listNode *ln;
+
+ listRewind(server.slaves,&li);
+ while((ln = listNext(&li))) {
+ redisClient *slave = listNodeValue(ln);
+ int events;
+
+ events = aeGetFileEvents(server.el,slave->fd);
+ if (events & AE_WRITABLE &&
+ slave->replstate == REDIS_REPL_ONLINE &&
+ listLength(slave->reply))
+ {
+ sendReplyToClient(server.el,slave->fd,slave,0);
+ }
+ }
+}
projects / redis.git / blobdiff