X-Git-Url: https://git.saurik.com/redis.git/blobdiff_plain/3a66edc7a43c3b32de1e9f609ddcc9d2c0fd4c2b..bcaa7a4ffab113115740ec47a6d1a923a7779bdf:/redis.c diff --git a/redis.c b/redis.c index e6b4455e..ce047a40 100644 --- a/redis.c +++ b/redis.c @@ -59,6 +59,7 @@ #include #include #include +#include #if defined(__sun) #include "solarisfixes.h" @@ -162,6 +163,14 @@ * Check vmFindContiguousPages() to know more about this magic numbers. */ #define REDIS_VM_MAX_NEAR_PAGES 65536 #define REDIS_VM_MAX_RANDOM_JUMP 4096 +#define REDIS_VM_MAX_THREADS 32 +#define REDIS_THREAD_STACK_SIZE (1024*1024*4) +/* The following is the number of completed I/O jobs to process when the + * handelr is called. 1 is the minimum, and also the default, as it allows + * to block as little as possible other accessing clients. While Virtual + * Memory I/O operations are performed by threads, this operations must + * be processed by the main thread when completed to take effect. */ +#define REDIS_MAX_COMPLETED_JOBS_PROCESSED 1 /* Client flags */ #define REDIS_CLOSE 1 /* This client connection should be closed ASAP */ @@ -170,6 +179,7 @@ #define REDIS_MONITOR 8 /* This client is a slave monitor, see MONITOR */ #define REDIS_MULTI 16 /* This client is in a MULTI context */ #define REDIS_BLOCKED 32 /* The client is waiting in a blocking operation */ +#define REDIS_IO_WAIT 64 /* The client is waiting for Virtual Memory I/O */ /* Slave replication state - slave side */ #define REDIS_REPL_NONE 0 /* No active replication */ @@ -197,8 +207,9 @@ /* Log levels */ #define REDIS_DEBUG 0 -#define REDIS_NOTICE 1 -#define REDIS_WARNING 2 +#define REDIS_VERBOSE 1 +#define REDIS_NOTICE 2 +#define REDIS_WARNING 3 /* Anti-warning macro... */ #define REDIS_NOTUSED(V) ((void) V) @@ -212,8 +223,8 @@ #define APPENDFSYNC_EVERYSEC 2 /* We can print the stacktrace, so our assert is defined this way: */ -#define redisAssert(_e) ((_e)?(void)0 : (_redisAssert(#_e),exit(1))) -static void _redisAssert(char *estr); +#define redisAssert(_e) ((_e)?(void)0 : (_redisAssert(#_e,__FILE__,__LINE__),exit(1))) +static void _redisAssert(char *estr, char *file, int line); /*================================= Data types ============================== */ @@ -231,8 +242,10 @@ typedef struct redisObject { void *ptr; unsigned char type; unsigned char encoding; - unsigned char storage; /* where? REDIS_VM_MEMORY, REDIS_VM_SWAPPED, ... */ - unsigned char notused; + unsigned char storage; /* If this object is a key, where is the value? + * REDIS_VM_MEMORY, REDIS_VM_SWAPPED, ... */ + unsigned char vtype; /* If this object is a key, and value is swapped out, + * this is the type of the swapped out object. */ int refcount; /* VM fields, this are only allocated if VM is active, otherwise the * object allocation function will just allocate @@ -300,6 +313,8 @@ typedef struct redisClient { int blockingkeysnum; /* Number of blocking keys */ time_t blockingto; /* Blocking operation timeout. If UNIX current time * is >= blockingto then the operation timed out. */ + list *io_keys; /* Keys this client is waiting to be loaded from the + * swap file in order to continue. */ } redisClient; struct saveparam { @@ -359,7 +374,7 @@ struct redisServer { redisClient *master; /* client that is master for this slave */ int replstate; unsigned int maxclients; - unsigned long maxmemory; + unsigned long long maxmemory; unsigned int blockedclients; /* Sort parameters - qsort_r() is only available under BSD so we * have to take this state global, in order to pass it to sortCompare() */ @@ -370,7 +385,7 @@ struct redisServer { int vm_enabled; off_t vm_page_size; off_t vm_pages; - long vm_max_memory; + unsigned long long vm_max_memory; /* Virtual memory state */ FILE *vm_fp; int vm_fd; @@ -378,6 +393,32 @@ struct redisServer { off_t vm_near_pages; /* Number of pages allocated sequentially */ unsigned char *vm_bitmap; /* Bitmap of free/used pages */ time_t unixtime; /* Unix time sampled every second. */ + /* Virtual memory I/O threads stuff */ + /* An I/O thread process an element taken from the io_jobs queue and + * put the result of the operation in the io_done list. While the + * job is being processed, it's put on io_processing queue. */ + list *io_newjobs; /* List of VM I/O jobs yet to be processed */ + list *io_processing; /* List of VM I/O jobs being processed */ + list *io_processed; /* List of VM I/O jobs already processed */ + list *io_clients; /* All the clients waiting for SWAP I/O operations */ + pthread_mutex_t io_mutex; /* lock to access io_jobs/io_done/io_thread_job */ + pthread_mutex_t obj_freelist_mutex; /* safe redis objects creation/free */ + pthread_mutex_t io_swapfile_mutex; /* So we can lseek + write */ + pthread_attr_t io_threads_attr; /* attributes for threads creation */ + int io_active_threads; /* Number of running I/O threads */ + int vm_max_threads; /* Max number of I/O threads running at the same time */ + /* Our main thread is blocked on the event loop, locking for sockets ready + * to be read or written, so when a threaded I/O operation is ready to be + * processed by the main thread, the I/O thread will use a unix pipe to + * awake the main thread. The followings are the two pipe FDs. */ + int io_ready_pipe_read; + int io_ready_pipe_write; + /* Virtual memory stats */ + unsigned long long vm_stats_used_pages; + unsigned long long vm_stats_swapped_objects; + unsigned long long vm_stats_swapouts; + unsigned long long vm_stats_swapins; + FILE *devnull; }; typedef void redisCommandProc(redisClient *c); @@ -443,6 +484,22 @@ struct sharedObjectsStruct { static double R_Zero, R_PosInf, R_NegInf, R_Nan; +/* VM threaded I/O request message */ +#define REDIS_IOJOB_LOAD 0 /* Load from disk to memory */ +#define REDIS_IOJOB_PREPARE_SWAP 1 /* Compute needed pages */ +#define REDIS_IOJOB_DO_SWAP 2 /* Swap from memory to disk */ +typedef struct iojon { + int type; /* Request type, REDIS_IOJOB_* */ + redisDb *db;/* Redis database */ + robj *key; /* This I/O request is about swapping this key */ + robj *val; /* the value to swap for REDIS_IOREQ_*_SWAP, otherwise this + * field is populated by the I/O thread for REDIS_IOREQ_LOAD. */ + off_t page; /* Swap page where to read/write the object */ + off_t pages; /* Swap pages needed to safe object. PREPARE_SWAP return val */ + int canceled; /* True if this command was canceled by blocking side of VM */ + pthread_t thread; /* ID of the thread processing this entry */ +} iojob; + /*================================ Prototypes =============================== */ static void freeStringObject(robj *o); @@ -457,6 +514,7 @@ static void addReplySds(redisClient *c, sds s); static void incrRefCount(robj *o); static int rdbSaveBackground(char *filename); static robj *createStringObject(char *ptr, size_t len); +static robj *dupStringObject(robj *o); static void replicationFeedSlaves(list *slaves, struct redisCommand *cmd, int dictid, robj **argv, int argc); static void feedAppendOnlyFile(struct redisCommand *cmd, int dictid, robj **argv, int argc); static int syncWithMaster(void); @@ -466,6 +524,7 @@ static robj *getDecodedObject(robj *o); static int removeExpire(redisDb *db, robj *key); static int expireIfNeeded(redisDb *db, robj *key); static int deleteIfVolatile(redisDb *db, robj *key); +static int deleteIfSwapped(redisDb *db, robj *key); static int deleteKey(redisDb *db, robj *key); static time_t getExpire(redisDb *db, robj *key); static int setExpire(redisDb *db, robj *key, time_t when); @@ -487,6 +546,24 @@ static void queueMultiCommand(redisClient *c, struct redisCommand *cmd); static void unblockClient(redisClient *c); static int handleClientsWaitingListPush(redisClient *c, robj *key, robj *ele); static void vmInit(void); +static void vmMarkPagesFree(off_t page, off_t count); +static robj *vmLoadObject(robj *key); +static robj *vmPreviewObject(robj *key); +static int vmSwapOneObjectBlocking(void); +static int vmSwapOneObjectThreaded(void); +static int vmCanSwapOut(void); +static int tryFreeOneObjectFromFreelist(void); +static void acceptHandler(aeEventLoop *el, int fd, void *privdata, int mask); +static void vmThreadedIOCompletedJob(aeEventLoop *el, int fd, void *privdata, int mask); +static void vmCancelThreadedIOJob(robj *o); +static void lockThreadedIO(void); +static void unlockThreadedIO(void); +static int vmSwapObjectThreaded(robj *key, robj *val, redisDb *db); +static void freeIOJob(iojob *j); +static void queueIOJob(iojob *j); +static int vmWriteObjectOnSwap(robj *o, off_t page); +static robj *vmReadObjectFromSwap(off_t page, int type); +static void waitZeroActiveThreads(void); static void authCommand(redisClient *c); static void pingCommand(redisClient *c); @@ -836,6 +913,7 @@ static void dictRedisObjectDestructor(void *privdata, void *val) { DICT_NOTUSED(privdata); + if (val == NULL) return; /* Values of swapped out keys as set to NULL */ decrRefCount(val); } @@ -874,6 +952,7 @@ static unsigned int dictEncObjHash(const void *key) { return hash; } +/* Sets type and expires */ static dictType setDictType = { dictEncObjHash, /* hash function */ NULL, /* key dup */ @@ -883,6 +962,7 @@ static dictType setDictType = { NULL /* val destructor */ }; +/* Sorted sets hash (note: a skiplist is used in addition to the hash table) */ static dictType zsetDictType = { dictEncObjHash, /* hash function */ NULL, /* key dup */ @@ -892,6 +972,7 @@ static dictType zsetDictType = { dictVanillaFree /* val destructor of malloc(sizeof(double)) */ }; +/* Db->dict */ static dictType hashDictType = { dictObjHash, /* hash function */ NULL, /* key dup */ @@ -901,6 +982,16 @@ static dictType hashDictType = { dictRedisObjectDestructor /* val destructor */ }; +/* Db->expires */ +static dictType keyptrDictType = { + dictObjHash, /* hash function */ + NULL, /* key dup */ + NULL, /* val dup */ + dictObjKeyCompare, /* key compare */ + dictRedisObjectDestructor, /* key destructor */ + NULL /* val destructor */ +}; + /* Keylist hash table type has unencoded redis objects as keys and * lists as values. It's used for blocking operations (BLPOP) */ static dictType keylistDictType = { @@ -930,16 +1021,17 @@ static void closeTimedoutClients(void) { redisClient *c; listNode *ln; time_t now = time(NULL); + listIter li; - listRewind(server.clients); - while ((ln = listYield(server.clients)) != NULL) { + listRewind(server.clients,&li); + while ((ln = listNext(&li)) != NULL) { c = listNodeValue(ln); if (server.maxidletime && !(c->flags & REDIS_SLAVE) && /* no timeout for slaves */ !(c->flags & REDIS_MASTER) && /* no timeout for masters */ (now - c->lastinteraction > server.maxidletime)) { - redisLog(REDIS_DEBUG,"Closing idle client"); + redisLog(REDIS_VERBOSE,"Closing idle client"); freeClient(c); } else if (c->flags & REDIS_BLOCKED) { if (c->blockingto != 0 && c->blockingto < now) { @@ -966,9 +1058,9 @@ static void tryResizeHashTables(void) { for (j = 0; j < server.dbnum; j++) { if (htNeedsResize(server.db[j].dict)) { - redisLog(REDIS_DEBUG,"The hash table %d is too sparse, resize it...",j); + redisLog(REDIS_VERBOSE,"The hash table %d is too sparse, resize it...",j); dictResize(server.db[j].dict); - redisLog(REDIS_DEBUG,"Hash table %d resized.",j); + redisLog(REDIS_VERBOSE,"Hash table %d resized.",j); } if (htNeedsResize(server.db[j].expires)) dictResize(server.db[j].expires); @@ -1082,7 +1174,7 @@ static int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientD used = dictSize(server.db[j].dict); vkeys = dictSize(server.db[j].expires); if (!(loops % 5) && (used || vkeys)) { - redisLog(REDIS_DEBUG,"DB %d: %lld keys (%lld volatile) in %lld slots HT.",j,used,vkeys,size); + redisLog(REDIS_VERBOSE,"DB %d: %lld keys (%lld volatile) in %lld slots HT.",j,used,vkeys,size); /* dictPrintStats(server.dict); */ } } @@ -1097,7 +1189,7 @@ static int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientD /* Show information about connected clients */ if (!(loops % 5)) { - redisLog(REDIS_DEBUG,"%d clients connected (%d slaves), %zu bytes in use, %d shared objects", + redisLog(REDIS_VERBOSE,"%d clients connected (%d slaves), %zu bytes in use, %d shared objects", listLength(server.clients)-listLength(server.slaves), listLength(server.slaves), server.usedmemory, @@ -1148,7 +1240,7 @@ static int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientD /* Continue to expire if at the end of the cycle more than 25% * of the keys were expired. */ do { - int num = dictSize(db->expires); + long num = dictSize(db->expires); time_t now = time(NULL); expired = 0; @@ -1168,6 +1260,32 @@ static int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientD } while (expired > REDIS_EXPIRELOOKUPS_PER_CRON/4); } + /* 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. */ + if (vmCanSwapOut()) { + while (server.vm_enabled && zmalloc_used_memory() > + server.vm_max_memory) + { + int retval; + + if (tryFreeOneObjectFromFreelist() == REDIS_OK) continue; + retval = (server.vm_max_threads == 0) ? + vmSwapOneObjectBlocking() : + vmSwapOneObjectThreaded(); + if (retval == REDIS_ERR && (loops % 30) == 0 && + zmalloc_used_memory() > + (server.vm_max_memory+server.vm_max_memory/10)) + { + redisLog(REDIS_WARNING,"WARNING: vm-max-memory limit exceeded by more than 10%% but unable to swap more objects out!"); + } + /* Note that when using threade I/O we free just one object, + * because anyway when the I/O thread in charge to swap this + * object out will finish, the handler of completed jobs + * will try to swap more objects if we are still out of memory. */ + if (retval == REDIS_ERR || server.vm_max_threads > 0) break; + } + } + /* Check if we should connect to a MASTER */ if (server.replstate == REDIS_REPL_CONNECT) { redisLog(REDIS_NOTICE,"Connecting to MASTER..."); @@ -1231,7 +1349,7 @@ static void resetServerSaveParams() { static void initServerConfig() { server.dbnum = REDIS_DEFAULT_DBNUM; server.port = REDIS_SERVERPORT; - server.verbosity = REDIS_DEBUG; + server.verbosity = REDIS_VERBOSE; server.maxidletime = REDIS_MAXIDLETIME; server.saveparams = NULL; server.logfile = NULL; /* NULL = log on standard output */ @@ -1257,6 +1375,7 @@ static void initServerConfig() { server.vm_page_size = 256; /* 256 bytes per page */ server.vm_pages = 1024*1024*100; /* 104 millions of pages */ server.vm_max_memory = 1024LL*1024*1024*1; /* 1 GB of RAM */ + server.vm_max_threads = 4; resetServerSaveParams(); @@ -1285,6 +1404,11 @@ static void initServer() { signal(SIGPIPE, SIG_IGN); setupSigSegvAction(); + server.devnull = fopen("/dev/null","w"); + if (server.devnull == NULL) { + redisLog(REDIS_WARNING, "Can't open /dev/null: %s", server.neterr); + exit(1); + } server.clients = listCreate(); server.slaves = listCreate(); server.monitors = listCreate(); @@ -1300,7 +1424,7 @@ static void initServer() { } for (j = 0; j < server.dbnum; j++) { server.db[j].dict = dictCreate(&hashDictType,NULL); - server.db[j].expires = dictCreate(&setDictType,NULL); + server.db[j].expires = dictCreate(&keyptrDictType,NULL); server.db[j].blockingkeys = dictCreate(&keylistDictType,NULL); server.db[j].id = j; } @@ -1316,6 +1440,8 @@ static void initServer() { server.stat_starttime = time(NULL); server.unixtime = time(NULL); aeCreateTimeEvent(server.el, 1, serverCron, NULL, NULL); + if (aeCreateFileEvent(server.el, server.fd, AE_READABLE, + acceptHandler, NULL) == AE_ERR) oom("creating file event"); if (server.appendonly) { server.appendfd = open(server.appendfilename,O_WRONLY|O_APPEND|O_CREAT,0644); @@ -1411,6 +1537,7 @@ static void loadServerConfig(char *filename) { } } else if (!strcasecmp(argv[0],"loglevel") && argc == 2) { if (!strcasecmp(argv[1],"debug")) server.verbosity = REDIS_DEBUG; + else if (!strcasecmp(argv[1],"verbose")) server.verbosity = REDIS_VERBOSE; else if (!strcasecmp(argv[1],"notice")) server.verbosity = REDIS_NOTICE; else if (!strcasecmp(argv[1],"warning")) server.verbosity = REDIS_WARNING; else { @@ -1497,6 +1624,14 @@ static void loadServerConfig(char *filename) { if ((server.vm_enabled = yesnotoi(argv[1])) == -1) { err = "argument must be 'yes' or 'no'"; goto loaderr; } + } else if (!strcasecmp(argv[0],"vm-max-memory") && argc == 2) { + server.vm_max_memory = strtoll(argv[1], NULL, 10); + } else if (!strcasecmp(argv[0],"vm-page-size") && argc == 2) { + server.vm_page_size = strtoll(argv[1], NULL, 10); + } else if (!strcasecmp(argv[0],"vm-pages") && argc == 2) { + server.vm_pages = strtoll(argv[1], NULL, 10); + } else if (!strcasecmp(argv[0],"vm-max-threads") && argc == 2) { + server.vm_max_threads = strtoll(argv[1], NULL, 10); } else { err = "Bad directive or wrong number of arguments"; goto loaderr; } @@ -1545,9 +1680,18 @@ static void freeClient(redisClient *c) { listRelease(c->reply); freeClientArgv(c); close(c->fd); + /* Remove from the list of clients */ ln = listSearchKey(server.clients,c); redisAssert(ln != NULL); listDelNode(server.clients,ln); + /* Remove from the list of clients waiting for VM operations */ + if (server.vm_enabled && listLength(c->io_keys)) { + ln = listSearchKey(server.io_clients,c); + if (ln) listDelNode(server.io_clients,ln); + listRelease(c->io_keys); + } + listRelease(c->io_keys); + /* Other cleanup */ if (c->flags & REDIS_SLAVE) { if (c->replstate == REDIS_REPL_SEND_BULK && c->repldbfd != -1) close(c->repldbfd); @@ -1571,10 +1715,11 @@ static void glueReplyBuffersIfNeeded(redisClient *c) { int copylen = 0; char buf[GLUEREPLY_UP_TO]; listNode *ln; + listIter li; robj *o; - listRewind(c->reply); - while((ln = listYield(c->reply))) { + listRewind(c->reply,&li); + while((ln = listNext(&li))) { int objlen; o = ln->value; @@ -1646,7 +1791,7 @@ static void sendReplyToClient(aeEventLoop *el, int fd, void *privdata, int mask) if (errno == EAGAIN) { nwritten = 0; } else { - redisLog(REDIS_DEBUG, + redisLog(REDIS_VERBOSE, "Error writing to client: %s", strerror(errno)); freeClient(c); return; @@ -1699,7 +1844,7 @@ static void sendReplyToClientWritev(aeEventLoop *el, int fd, void *privdata, int /* write all collected blocks at once */ if((nwritten = writev(fd, iov, ion)) < 0) { if (errno != EAGAIN) { - redisLog(REDIS_DEBUG, + redisLog(REDIS_VERBOSE, "Error writing to client: %s", strerror(errno)); freeClient(c); return; @@ -1936,6 +2081,7 @@ static int processCommand(redisClient *c) { static void replicationFeedSlaves(list *slaves, struct redisCommand *cmd, int dictid, robj **argv, int argc) { listNode *ln; + listIter li; int outc = 0, j; robj **outv; /* (args*2)+1 is enough room for args, spaces, newlines */ @@ -1966,8 +2112,8 @@ static void replicationFeedSlaves(list *slaves, struct redisCommand *cmd, int di * be sure to free objects if there is no slave in a replication state * able to be feed with commands */ for (j = 0; j < outc; j++) incrRefCount(outv[j]); - listRewind(slaves); - while((ln = listYield(slaves))) { + listRewind(slaves,&li); + while((ln = listNext(&li))) { redisClient *slave = ln->value; /* Don't feed slaves that are still waiting for BGSAVE to start */ @@ -2011,7 +2157,7 @@ again: * would not be called at all, but after the execution of the first commands * in the input buffer the client may be blocked, and the "goto again" * will try to reiterate. The following line will make it return asap. */ - if (c->flags & REDIS_BLOCKED) return; + if (c->flags & REDIS_BLOCKED || c->flags & REDIS_IO_WAIT) return; if (c->bulklen == -1) { /* Read the first line of the query */ char *p = strchr(c->querybuf,'\n'); @@ -2060,7 +2206,7 @@ again: } return; } else if (sdslen(c->querybuf) >= REDIS_REQUEST_MAX_SIZE) { - redisLog(REDIS_DEBUG, "Client protocol error"); + redisLog(REDIS_VERBOSE, "Client protocol error"); freeClient(c); return; } @@ -2097,12 +2243,12 @@ static void readQueryFromClient(aeEventLoop *el, int fd, void *privdata, int mas if (errno == EAGAIN) { nread = 0; } else { - redisLog(REDIS_DEBUG, "Reading from client: %s",strerror(errno)); + redisLog(REDIS_VERBOSE, "Reading from client: %s",strerror(errno)); freeClient(c); return; } } else if (nread == 0) { - redisLog(REDIS_DEBUG, "Client closed connection"); + redisLog(REDIS_VERBOSE, "Client closed connection"); freeClient(c); return; } @@ -2148,10 +2294,12 @@ static redisClient *createClient(int fd) { c->authenticated = 0; c->replstate = REDIS_REPL_NONE; c->reply = listCreate(); - c->blockingkeys = NULL; - c->blockingkeysnum = 0; listSetFreeMethod(c->reply,decrRefCount); listSetDupMethod(c->reply,dupClientReplyValue); + c->blockingkeys = NULL; + c->blockingkeysnum = 0; + c->io_keys = listCreate(); + listSetFreeMethod(c->io_keys,decrRefCount); if (aeCreateFileEvent(server.el, c->fd, AE_READABLE, readQueryFromClient, c) == AE_ERR) { freeClient(c); @@ -2168,6 +2316,11 @@ static void addReply(redisClient *c, robj *obj) { c->replstate == REDIS_REPL_ONLINE) && aeCreateFileEvent(server.el, c->fd, AE_WRITABLE, sendReplyToClient, c) == AE_ERR) return; + + if (server.vm_enabled && obj->storage != REDIS_VM_MEMORY) { + obj = dupStringObject(obj); + obj->refcount = 0; /* getDecodedObject() will increment the refcount */ + } listAddNodeTail(c->reply,getDecodedObject(obj)); } @@ -2216,10 +2369,10 @@ static void acceptHandler(aeEventLoop *el, int fd, void *privdata, int mask) { cfd = anetAccept(server.neterr, fd, cip, &cport); if (cfd == AE_ERR) { - redisLog(REDIS_DEBUG,"Accepting client connection: %s", server.neterr); + redisLog(REDIS_VERBOSE,"Accepting client connection: %s", server.neterr); return; } - redisLog(REDIS_DEBUG,"Accepted %s:%d", cip, cport); + redisLog(REDIS_VERBOSE,"Accepted %s:%d", cip, cport); if ((c = createClient(cfd)) == NULL) { redisLog(REDIS_WARNING,"Error allocating resoures for the client"); close(cfd); /* May be already closed, just ingore errors */ @@ -2247,12 +2400,15 @@ static void acceptHandler(aeEventLoop *el, int fd, void *privdata, int mask) { static robj *createObject(int type, void *ptr) { robj *o; + if (server.vm_enabled) pthread_mutex_lock(&server.obj_freelist_mutex); if (listLength(server.objfreelist)) { listNode *head = listFirst(server.objfreelist); o = listNodeValue(head); listDelNode(server.objfreelist,head); + if (server.vm_enabled) pthread_mutex_unlock(&server.obj_freelist_mutex); } else { if (server.vm_enabled) { + pthread_mutex_unlock(&server.obj_freelist_mutex); o = zmalloc(sizeof(*o)); } else { o = zmalloc(sizeof(*o)-sizeof(struct redisObjectVM)); @@ -2273,6 +2429,11 @@ static robj *createStringObject(char *ptr, size_t len) { return createObject(REDIS_STRING,sdsnewlen(ptr,len)); } +static robj *dupStringObject(robj *o) { + assert(o->encoding == REDIS_ENCODING_RAW); + return createStringObject(o->ptr,sdslen(o->ptr)); +} + static robj *createListObject(void) { list *l = listCreate(); @@ -2320,21 +2481,36 @@ static void freeHashObject(robj *o) { } static void incrRefCount(robj *o) { + redisAssert(!server.vm_enabled || o->storage == REDIS_VM_MEMORY); o->refcount++; -#ifdef DEBUG_REFCOUNT - if (o->type == REDIS_STRING) - printf("Increment '%s'(%p), now is: %d\n",o->ptr,o,o->refcount); -#endif } static void decrRefCount(void *obj) { robj *o = obj; -#ifdef DEBUG_REFCOUNT - if (o->type == REDIS_STRING) - printf("Decrement '%s'(%p), now is: %d\n",o->ptr,o,o->refcount-1); -#endif + /* Object is swapped out, or in the process of being loaded. */ + if (server.vm_enabled && + (o->storage == REDIS_VM_SWAPPED || o->storage == REDIS_VM_LOADING)) + { + if (o->storage == REDIS_VM_SWAPPED || o->storage == REDIS_VM_LOADING) { + redisAssert(o->refcount == 1); + } + if (o->storage == REDIS_VM_LOADING) vmCancelThreadedIOJob(obj); + redisAssert(o->type == REDIS_STRING); + freeStringObject(o); + vmMarkPagesFree(o->vm.page,o->vm.usedpages); + pthread_mutex_lock(&server.obj_freelist_mutex); + if (listLength(server.objfreelist) > REDIS_OBJFREELIST_MAX || + !listAddNodeHead(server.objfreelist,o)) + zfree(o); + pthread_mutex_unlock(&server.obj_freelist_mutex); + server.vm_stats_swapped_objects--; + return; + } + /* Object is in memory, or in the process of being swapped out. */ if (--(o->refcount) == 0) { + if (server.vm_enabled && o->storage == REDIS_VM_SWAPPING) + vmCancelThreadedIOJob(obj); switch(o->type) { case REDIS_STRING: freeStringObject(o); break; case REDIS_LIST: freeListObject(o); break; @@ -2343,20 +2519,38 @@ static void decrRefCount(void *obj) { case REDIS_HASH: freeHashObject(o); break; default: redisAssert(0 != 0); break; } + if (server.vm_enabled) pthread_mutex_lock(&server.obj_freelist_mutex); if (listLength(server.objfreelist) > REDIS_OBJFREELIST_MAX || !listAddNodeHead(server.objfreelist,o)) zfree(o); + if (server.vm_enabled) pthread_mutex_unlock(&server.obj_freelist_mutex); } } static robj *lookupKey(redisDb *db, robj *key) { dictEntry *de = dictFind(db->dict,key); if (de) { - robj *o = dictGetEntryVal(de); + robj *key = dictGetEntryKey(de); + robj *val = dictGetEntryVal(de); - /* Update the access time of the key for the aging algorithm. */ - if (server.vm_enabled) o->vm.atime = server.unixtime; - return o; + if (server.vm_enabled) { + if (key->storage == REDIS_VM_MEMORY || + key->storage == REDIS_VM_SWAPPING) + { + /* If we were swapping the object out, stop it, this key + * was requested. */ + if (key->storage == REDIS_VM_SWAPPING) + vmCancelThreadedIOJob(key); + /* Update the access time of the key for the aging algorithm. */ + key->vm.atime = server.unixtime; + } else { + /* Our value was swapped on disk. Bring it at home. */ + redisAssert(val == NULL); + val = vmLoadObject(key); + dictGetEntryVal(de) = val; + } + } + return val; } else { return NULL; } @@ -2625,6 +2819,8 @@ static int rdbSaveLzfStringObject(FILE *fp, robj *obj) { outlen = sdslen(obj->ptr)-4; if (outlen <= 0) return 0; if ((out = zmalloc(outlen+1)) == NULL) return 0; + printf("Calling LZF with ptr: %p\n", (void*)obj->ptr); + fflush(stdout); comprlen = lzf_compress(obj->ptr, sdslen(obj->ptr), out, outlen); if (comprlen == 0) { zfree(out); @@ -2682,9 +2878,18 @@ static int rdbSaveStringObjectRaw(FILE *fp, robj *obj) { static int rdbSaveStringObject(FILE *fp, robj *obj) { int retval; - obj = getDecodedObject(obj); - retval = rdbSaveStringObjectRaw(fp,obj); - decrRefCount(obj); + /* Avoid incr/decr ref count business when possible. + * This plays well with copy-on-write given that we are probably + * in a child process (BGSAVE). Also this makes sure key objects + * of swapped objects are not incRefCount-ed (an assert does not allow + * this in order to avoid bugs) */ + if (obj->encoding != REDIS_ENCODING_RAW) { + obj = getDecodedObject(obj); + retval = rdbSaveStringObjectRaw(fp,obj); + decrRefCount(obj); + } else { + retval = rdbSaveStringObjectRaw(fp,obj); + } return retval; } @@ -2723,11 +2928,12 @@ static int rdbSaveObject(FILE *fp, robj *o) { } else if (o->type == REDIS_LIST) { /* Save a list value */ list *list = o->ptr; + listIter li; listNode *ln; - listRewind(list); if (rdbSaveLen(fp,listLength(list)) == -1) return -1; - while((ln = listYield(list))) { + listRewind(list,&li); + while((ln = listNext(&li))) { robj *eleobj = listNodeValue(ln); if (rdbSaveStringObject(fp,eleobj) == -1) return -1; @@ -2770,20 +2976,16 @@ static int rdbSaveObject(FILE *fp, robj *o) { * the rdbSaveObject() function. Currently we use a trick to get * this length with very little changes to the code. In the future * we could switch to a faster solution. */ -static off_t rdbSavedObjectLen(robj *o) { - static FILE *fp = NULL; - - if (fp == NULL) fp = fopen("/dev/null","w"); - assert(fp != NULL); - +static off_t rdbSavedObjectLen(robj *o, FILE *fp) { + if (fp == NULL) fp = server.devnull; rewind(fp); assert(rdbSaveObject(fp,o) != 1); return ftello(fp); } /* Return the number of pages required to save this object in the swap file */ -static off_t rdbSavedObjectPages(robj *o) { - off_t bytes = rdbSavedObjectLen(o); +static off_t rdbSavedObjectPages(robj *o, FILE *fp) { + off_t bytes = rdbSavedObjectLen(o,fp); return (bytes+(server.vm_page_size-1))/server.vm_page_size; } @@ -2831,11 +3033,26 @@ static int rdbSave(char *filename) { if (rdbSaveType(fp,REDIS_EXPIRETIME) == -1) goto werr; if (rdbSaveTime(fp,expiretime) == -1) goto werr; } - /* Save the key and associated value */ - if (rdbSaveType(fp,o->type) == -1) goto werr; - if (rdbSaveStringObject(fp,key) == -1) goto werr; - /* Save the actual value */ - if (rdbSaveObject(fp,o) == -1) goto werr; + /* Save the key and associated value. This requires special + * handling if the value is swapped out. */ + if (!server.vm_enabled || key->storage == REDIS_VM_MEMORY || + key->storage == REDIS_VM_SWAPPING) { + /* Save type, key, value */ + if (rdbSaveType(fp,o->type) == -1) goto werr; + if (rdbSaveStringObject(fp,key) == -1) goto werr; + if (rdbSaveObject(fp,o) == -1) goto werr; + } else { + /* REDIS_VM_SWAPPED or REDIS_VM_LOADING */ + robj *po; + /* Get a preview of the object in memory */ + po = vmPreviewObject(key); + /* Save type, key, value */ + if (rdbSaveType(fp,key->vtype) == -1) goto werr; + if (rdbSaveStringObject(fp,key) == -1) goto werr; + if (rdbSaveObject(fp,po) == -1) goto werr; + /* Remove the loaded object from memory */ + decrRefCount(po); + } } dictReleaseIterator(di); } @@ -2871,6 +3088,7 @@ static int rdbSaveBackground(char *filename) { pid_t childpid; if (server.bgsavechildpid != -1) return REDIS_ERR; + if (server.vm_enabled) waitZeroActiveThreads(); if ((childpid = fork()) == 0) { /* Child */ close(server.fd); @@ -3094,6 +3312,7 @@ static int rdbLoad(char *filename) { redisDb *db = server.db+0; char buf[1024]; time_t expiretime = -1, now = time(NULL); + long long loadedkeys = 0; fp = fopen(filename,"r"); if (!fp) return REDIS_ERR; @@ -3151,6 +3370,13 @@ static int rdbLoad(char *filename) { expiretime = -1; } keyobj = o = NULL; + /* Handle swapping while loading big datasets when VM is on */ + loadedkeys++; + if (server.vm_enabled && (loadedkeys % 5000) == 0) { + while (zmalloc_used_memory() > server.vm_max_memory) { + if (vmSwapOneObjectBlocking() == REDIS_ERR) break; + } + } } fclose(fp); return REDIS_OK; @@ -3193,6 +3419,12 @@ static void setGenericCommand(redisClient *c, int nx) { retval = dictAdd(c->db->dict,c->argv[1],c->argv[2]); if (retval == DICT_ERR) { if (!nx) { + /* If the key is about a swapped value, we want a new key object + * to overwrite the old. So we delete the old key in the database. + * This will also make sure that swap pages about the old object + * will be marked as free. */ + if (deleteIfSwapped(c->db,c->argv[1])) + incrRefCount(c->argv[1]); dictReplace(c->db->dict,c->argv[1],c->argv[2]); incrRefCount(c->argv[2]); } else { @@ -5138,9 +5370,10 @@ static void sortCommand(redisClient *c) { if (sortval->type == REDIS_LIST) { list *list = sortval->ptr; listNode *ln; + listIter li; - listRewind(list); - while((ln = listYield(list))) { + listRewind(list,&li); + while((ln = listNext(&li))) { robj *ele = ln->value; vector[j].obj = ele; vector[j].u.score = 0; @@ -5236,13 +5469,15 @@ static void sortCommand(redisClient *c) { addReplySds(c,sdscatprintf(sdsempty(),"*%d\r\n",outputlen)); for (j = start; j <= end; j++) { listNode *ln; + listIter li; + if (!getop) { addReplyBulkLen(c,vector[j].obj); addReply(c,vector[j].obj); addReply(c,shared.crlf); } - listRewind(operations); - while((ln = listYield(operations))) { + listRewind(operations,&li); + while((ln = listNext(&li))) { redisSortOperation *sop = ln->value; robj *val = lookupKeyByPattern(c->db,sop->pattern, vector[j].obj); @@ -5267,12 +5502,14 @@ static void sortCommand(redisClient *c) { /* STORE option specified, set the sorting result as a List object */ for (j = start; j <= end; j++) { listNode *ln; + listIter li; + if (!getop) { listAddNodeTail(listPtr,vector[j].obj); incrRefCount(vector[j].obj); } - listRewind(operations); - while((ln = listYield(operations))) { + listRewind(operations,&li); + while((ln = listNext(&li))) { redisSortOperation *sop = ln->value; robj *val = lookupKeyByPattern(c->db,sop->pattern, vector[j].obj); @@ -5309,6 +5546,27 @@ static void sortCommand(redisClient *c) { zfree(vector); } +/* Convert an amount of bytes into a human readable string in the form + * of 100B, 2G, 100M, 4K, and so forth. */ +static void bytesToHuman(char *s, unsigned long long n) { + double d; + + if (n < 1024) { + /* Bytes */ + sprintf(s,"%lluB",n); + return; + } else if (n < (1024*1024)) { + d = (double)n/(1024); + sprintf(s,"%.2fK",d); + } else if (n < (1024LL*1024*1024)) { + d = (double)n/(1024*1024); + sprintf(s,"%.2fM",d); + } else if (n < (1024LL*1024*1024*1024)) { + d = (double)n/(1024LL*1024*1024); + sprintf(s,"%.2fM",d); + } +} + /* Create the string returned by the INFO command. This is decoupled * by the INFO command itself as we need to report the same information * on memory corruption problems. */ @@ -5316,39 +5574,47 @@ static sds genRedisInfoString(void) { sds info; time_t uptime = time(NULL)-server.stat_starttime; int j; - + char hmem[64]; + + bytesToHuman(hmem,server.usedmemory); info = sdscatprintf(sdsempty(), "redis_version:%s\r\n" "arch_bits:%s\r\n" "multiplexing_api:%s\r\n" + "process_id:%ld\r\n" "uptime_in_seconds:%ld\r\n" "uptime_in_days:%ld\r\n" "connected_clients:%d\r\n" "connected_slaves:%d\r\n" "blocked_clients:%d\r\n" "used_memory:%zu\r\n" + "used_memory_human:%s\r\n" "changes_since_last_save:%lld\r\n" "bgsave_in_progress:%d\r\n" "last_save_time:%ld\r\n" "bgrewriteaof_in_progress:%d\r\n" "total_connections_received:%lld\r\n" "total_commands_processed:%lld\r\n" + "vm_enabled:%d\r\n" "role:%s\r\n" ,REDIS_VERSION, (sizeof(long) == 8) ? "64" : "32", aeGetApiName(), + (long) getpid(), uptime, uptime/(3600*24), listLength(server.clients)-listLength(server.slaves), listLength(server.slaves), server.blockedclients, server.usedmemory, + hmem, server.dirty, server.bgsavechildpid != -1, server.lastsave, server.bgrewritechildpid != -1, server.stat_numconnections, server.stat_numcommands, + server.vm_enabled != 0, server.masterhost == NULL ? "master" : "slave" ); if (server.masterhost) { @@ -5364,6 +5630,34 @@ static sds genRedisInfoString(void) { server.master ? ((int)(time(NULL)-server.master->lastinteraction)) : -1 ); } + if (server.vm_enabled) { + info = sdscatprintf(info, + "vm_conf_max_memory:%llu\r\n" + "vm_conf_page_size:%llu\r\n" + "vm_conf_pages:%llu\r\n" + "vm_stats_used_pages:%llu\r\n" + "vm_stats_swapped_objects:%llu\r\n" + "vm_stats_swappin_count:%llu\r\n" + "vm_stats_swappout_count:%llu\r\n" + "vm_stats_io_newjobs_len:%lu\r\n" + "vm_stats_io_processing_len:%lu\r\n" + "vm_stats_io_processed_len:%lu\r\n" + "vm_stats_io_waiting_clients:%lu\r\n" + "vm_stats_io_active_threads:%lu\r\n" + ,(unsigned long long) server.vm_max_memory, + (unsigned long long) server.vm_page_size, + (unsigned long long) server.vm_pages, + (unsigned long long) server.vm_stats_used_pages, + (unsigned long long) server.vm_stats_swapped_objects, + (unsigned long long) server.vm_stats_swapins, + (unsigned long long) server.vm_stats_swapouts, + (unsigned long) listLength(server.io_newjobs), + (unsigned long) listLength(server.io_processing), + (unsigned long) listLength(server.io_processed), + (unsigned long) listLength(server.io_clients), + (unsigned long) server.io_active_threads + ); + } for (j = 0; j < server.dbnum; j++) { long long keys, vkeys; @@ -5855,9 +6149,10 @@ static void syncCommand(redisClient *c) { * registering differences since the server forked to save */ redisClient *slave; listNode *ln; + listIter li; - listRewind(server.slaves); - while((ln = listYield(server.slaves))) { + listRewind(server.slaves,&li); + while((ln = listNext(&li))) { slave = ln->value; if (slave->replstate == REDIS_REPL_WAIT_BGSAVE_END) break; } @@ -5924,7 +6219,7 @@ static void sendBulkToSlave(aeEventLoop *el, int fd, void *privdata, int mask) { return; } if ((nwritten = write(fd,buf,buflen)) == -1) { - redisLog(REDIS_DEBUG,"Write error sending DB to slave: %s", + redisLog(REDIS_VERBOSE,"Write error sending DB to slave: %s", strerror(errno)); freeClient(slave); return; @@ -5954,9 +6249,10 @@ static void sendBulkToSlave(aeEventLoop *el, int fd, void *privdata, int mask) { static void updateSlavesWaitingBgsave(int bgsaveerr) { listNode *ln; int startbgsave = 0; + listIter li; - listRewind(server.slaves); - while((ln = listYield(server.slaves))) { + listRewind(server.slaves,&li); + while((ln = listNext(&li))) { redisClient *slave = ln->value; if (slave->replstate == REDIS_REPL_WAIT_BGSAVE_START) { @@ -5988,9 +6284,11 @@ static void updateSlavesWaitingBgsave(int bgsaveerr) { } if (startbgsave) { if (rdbSaveBackground(server.dbfilename) != REDIS_OK) { - listRewind(server.slaves); + listIter li; + + listRewind(server.slaves,&li); redisLog(REDIS_WARNING,"SYNC failed. BGSAVE failed"); - while((ln = listYield(server.slaves))) { + while((ln = listNext(&li))) { redisClient *slave = ln->value; if (slave->replstate == REDIS_REPL_WAIT_BGSAVE_START) @@ -6128,6 +6426,27 @@ static void slaveofCommand(redisClient *c) { /* ============================ Maxmemory directive ======================== */ +/* Try to free one object form the pre-allocated objects free list. + * This is useful under low mem conditions as by default we take 1 million + * free objects allocated. On success REDIS_OK is returned, otherwise + * REDIS_ERR. */ +static int tryFreeOneObjectFromFreelist(void) { + robj *o; + + if (server.vm_enabled) pthread_mutex_lock(&server.obj_freelist_mutex); + if (listLength(server.objfreelist)) { + listNode *head = listFirst(server.objfreelist); + o = listNodeValue(head); + listDelNode(server.objfreelist,head); + if (server.vm_enabled) pthread_mutex_unlock(&server.obj_freelist_mutex); + zfree(o); + return REDIS_OK; + } else { + if (server.vm_enabled) pthread_mutex_unlock(&server.obj_freelist_mutex); + return REDIS_ERR; + } +} + /* This function gets called when 'maxmemory' is set on the config file to limit * the max memory used by the server, and we are out of memory. * This function will try to, in order: @@ -6141,40 +6460,32 @@ static void slaveofCommand(redisClient *c) { */ static void freeMemoryIfNeeded(void) { while (server.maxmemory && zmalloc_used_memory() > server.maxmemory) { - if (listLength(server.objfreelist)) { - robj *o; - - listNode *head = listFirst(server.objfreelist); - o = listNodeValue(head); - listDelNode(server.objfreelist,head); - zfree(o); - } else { - int j, k, freed = 0; - - for (j = 0; j < server.dbnum; j++) { - int minttl = -1; - robj *minkey = NULL; - struct dictEntry *de; - - if (dictSize(server.db[j].expires)) { - freed = 1; - /* From a sample of three keys drop the one nearest to - * the natural expire */ - for (k = 0; k < 3; k++) { - time_t t; - - de = dictGetRandomKey(server.db[j].expires); - t = (time_t) dictGetEntryVal(de); - if (minttl == -1 || t < minttl) { - minkey = dictGetEntryKey(de); - minttl = t; - } + int j, k, freed = 0; + + if (tryFreeOneObjectFromFreelist() == REDIS_OK) continue; + for (j = 0; j < server.dbnum; j++) { + int minttl = -1; + robj *minkey = NULL; + struct dictEntry *de; + + if (dictSize(server.db[j].expires)) { + freed = 1; + /* From a sample of three keys drop the one nearest to + * the natural expire */ + for (k = 0; k < 3; k++) { + time_t t; + + de = dictGetRandomKey(server.db[j].expires); + t = (time_t) dictGetEntryVal(de); + if (minttl == -1 || t < minttl) { + minkey = dictGetEntryKey(de); + minttl = t; } - deleteKey(server.db+j,minkey); } + deleteKey(server.db+j,minkey); } - if (!freed) return; /* nothing to free... */ } + if (!freed) return; /* nothing to free... */ } } @@ -6298,6 +6609,7 @@ int loadAppendOnlyFile(char *filename) { struct redisClient *fakeClient; FILE *fp = fopen(filename,"r"); struct redis_stat sb; + unsigned long long loadedkeys = 0; if (redis_fstat(fileno(fp),&sb) != -1 && sb.st_size == 0) return REDIS_ERR; @@ -6359,6 +6671,13 @@ int loadAppendOnlyFile(char *filename) { /* Clean up, ready for the next command */ for (j = 0; j < argc; j++) decrRefCount(argv[j]); zfree(argv); + /* Handle swapping while loading big datasets when VM is on */ + loadedkeys++; + if (server.vm_enabled && (loadedkeys % 5000) == 0) { + while (zmalloc_used_memory() > server.vm_max_memory) { + if (vmSwapOneObjectBlocking() == REDIS_ERR) break; + } + } } fclose(fp); freeFakeClient(fakeClient); @@ -6379,16 +6698,26 @@ fmterr: /* Write an object into a file in the bulk format $\r\n\r\n */ static int fwriteBulk(FILE *fp, robj *obj) { char buf[128]; - obj = getDecodedObject(obj); + int decrrc = 0; + + /* Avoid the incr/decr ref count business if possible to help + * copy-on-write (we are often in a child process when this function + * is called). + * Also makes sure that key objects don't get incrRefCount-ed when VM + * is enabled */ + if (obj->encoding != REDIS_ENCODING_RAW) { + obj = getDecodedObject(obj); + decrrc = 1; + } snprintf(buf,sizeof(buf),"$%ld\r\n",(long)sdslen(obj->ptr)); if (fwrite(buf,strlen(buf),1,fp) == 0) goto err; if (sdslen(obj->ptr) && fwrite(obj->ptr,sdslen(obj->ptr),1,fp) == 0) goto err; if (fwrite("\r\n",2,1,fp) == 0) goto err; - decrRefCount(obj); + if (decrrc) decrRefCount(obj); return 1; err: - decrRefCount(obj); + if (decrrc) decrRefCount(obj); return 0; } @@ -6449,9 +6778,24 @@ static int rewriteAppendOnlyFile(char *filename) { /* Iterate this DB writing every entry */ while((de = dictNext(di)) != NULL) { - robj *key = dictGetEntryKey(de); - robj *o = dictGetEntryVal(de); - time_t expiretime = getExpire(db,key); + robj *key, *o; + time_t expiretime; + int swapped; + + key = dictGetEntryKey(de); + /* If the value for this key is swapped, load a preview in memory. + * We use a "swapped" flag to remember if we need to free the + * value object instead to just increment the ref count anyway + * in order to avoid copy-on-write of pages if we are forked() */ + if (!server.vm_enabled || key->storage == REDIS_VM_MEMORY || + key->storage == REDIS_VM_SWAPPING) { + o = dictGetEntryVal(de); + swapped = 0; + } else { + o = vmPreviewObject(key); + swapped = 1; + } + expiretime = getExpire(db,key); /* Save the key and associated value */ if (o->type == REDIS_STRING) { @@ -6465,9 +6809,10 @@ static int rewriteAppendOnlyFile(char *filename) { /* Emit the RPUSHes needed to rebuild the list */ list *list = o->ptr; listNode *ln; + listIter li; - listRewind(list); - while((ln = listYield(list))) { + listRewind(list,&li); + while((ln = listNext(&li))) { char cmd[]="*3\r\n$5\r\nRPUSH\r\n"; robj *eleobj = listNodeValue(ln); @@ -6519,6 +6864,7 @@ static int rewriteAppendOnlyFile(char *filename) { if (fwriteBulk(fp,key) == 0) goto werr; if (fwriteBulkLong(fp,expiretime) == 0) goto werr; } + if (swapped) decrRefCount(o); } dictReleaseIterator(di); } @@ -6562,6 +6908,7 @@ static int rewriteAppendOnlyFileBackground(void) { pid_t childpid; if (server.bgrewritechildpid != -1) return REDIS_ERR; + if (server.vm_enabled) waitZeroActiveThreads(); if ((childpid = fork()) == 0) { /* Child */ char tmpfile[256]; @@ -6614,9 +6961,32 @@ static void aofRemoveTempFile(pid_t childpid) { unlink(tmpfile); } -/* =============================== Virtual Memory =========================== */ +/* Virtual Memory is composed mainly of two subsystems: + * - Blocking Virutal Memory + * - Threaded Virtual Memory I/O + * The two parts are not fully decoupled, but functions are split among two + * different sections of the source code (delimited by comments) in order to + * make more clear what functionality is about the blocking VM and what about + * the threaded (not blocking) VM. + * + * Redis VM design: + * + * Redis VM is a blocking VM (one that blocks reading swapped values from + * disk into memory when a value swapped out is needed in memory) that is made + * unblocking by trying to examine the command argument vector in order to + * load in background values that will likely be needed in order to exec + * the command. The command is executed only once all the relevant keys + * are loaded into memory. + * + * This basically is almost as simple of a blocking VM, but almost as parallel + * as a fully non-blocking VM. + */ + +/* =================== Virtual Memory - Blocking Side ====================== */ static void vmInit(void) { off_t totsize; + int pipefds[2]; + size_t stacksize; server.vm_fp = fopen("/tmp/redisvm","w+b"); if (server.vm_fp == NULL) { @@ -6626,6 +6996,10 @@ static void vmInit(void) { server.vm_fd = fileno(server.vm_fp); server.vm_next_page = 0; server.vm_near_pages = 0; + server.vm_stats_used_pages = 0; + server.vm_stats_swapped_objects = 0; + server.vm_stats_swapouts = 0; + server.vm_stats_swapins = 0; totsize = server.vm_pages*server.vm_page_size; redisLog(REDIS_NOTICE,"Allocating %lld bytes of swap file",totsize); if (ftruncate(server.vm_fd,totsize) == -1) { @@ -6635,11 +7009,40 @@ static void vmInit(void) { } else { redisLog(REDIS_NOTICE,"Swap file allocated with success"); } - server.vm_bitmap = zmalloc((server.vm_near_pages+7)/8); - memset(server.vm_bitmap,0,(server.vm_near_pages+7)/8); + server.vm_bitmap = zmalloc((server.vm_pages+7)/8); + redisLog(REDIS_VERBOSE,"Allocated %lld bytes page table for %lld pages", + (long long) (server.vm_pages+7)/8, server.vm_pages); + memset(server.vm_bitmap,0,(server.vm_pages+7)/8); /* Try to remove the swap file, so the OS will really delete it from the * file system when Redis exists. */ unlink("/tmp/redisvm"); + + /* Initialize threaded I/O (used by Virtual Memory) */ + server.io_newjobs = listCreate(); + server.io_processing = listCreate(); + server.io_processed = listCreate(); + server.io_clients = listCreate(); + pthread_mutex_init(&server.io_mutex,NULL); + pthread_mutex_init(&server.obj_freelist_mutex,NULL); + pthread_mutex_init(&server.io_swapfile_mutex,NULL); + server.io_active_threads = 0; + if (pipe(pipefds) == -1) { + redisLog(REDIS_WARNING,"Unable to intialized VM: pipe(2): %s. Exiting." + ,strerror(errno)); + exit(1); + } + server.io_ready_pipe_read = pipefds[0]; + server.io_ready_pipe_write = pipefds[1]; + redisAssert(anetNonBlock(NULL,server.io_ready_pipe_read) != ANET_ERR); + /* LZF requires a lot of stack */ + pthread_attr_init(&server.io_threads_attr); + pthread_attr_getstacksize(&server.io_threads_attr, &stacksize); + while (stacksize < REDIS_THREAD_STACK_SIZE) stacksize *= 2; + pthread_attr_setstacksize(&server.io_threads_attr, stacksize); + /* Listen for events in the threaded I/O pipe */ + if (aeCreateFileEvent(server.el, server.io_ready_pipe_read, AE_READABLE, + vmThreadedIOCompletedJob, NULL) == AE_ERR) + oom("creating file event"); } /* Mark the page as used */ @@ -6647,6 +7050,8 @@ static void vmMarkPageUsed(off_t page) { off_t byte = page/8; int bit = page&7; server.vm_bitmap[byte] |= 1<= server.vm_pages) { this -= server.vm_pages; @@ -6725,7 +7133,8 @@ static int vmFindContiguousPages(off_t *first, int n) { numfree++; /* Already got N free pages? Return to the caller, with success */ if (numfree == n) { - *first = this; + *first = this-(n-1); + server.vm_next_page = this+1; return REDIS_OK; } } else { @@ -6750,54 +7159,572 @@ static int vmFindContiguousPages(off_t *first, int n) { return REDIS_ERR; } +/* Write the specified object at the specified page of the swap file */ +static int vmWriteObjectOnSwap(robj *o, off_t page) { + if (server.vm_enabled) pthread_mutex_lock(&server.io_swapfile_mutex); + if (fseeko(server.vm_fp,page*server.vm_page_size,SEEK_SET) == -1) { + if (server.vm_enabled) pthread_mutex_unlock(&server.io_swapfile_mutex); + redisLog(REDIS_WARNING, + "Critical VM problem in vmSwapObjectBlocking(): can't seek: %s", + strerror(errno)); + return REDIS_ERR; + } + rdbSaveObject(server.vm_fp,o); + if (server.vm_enabled) pthread_mutex_unlock(&server.io_swapfile_mutex); + return REDIS_OK; +} + /* Swap the 'val' object relative to 'key' into disk. Store all the information * needed to later retrieve the object into the key object. * If we can't find enough contiguous empty pages to swap the object on disk * REDIS_ERR is returned. */ -static int vmSwapObject(robj *key, robj *val) { - off_t pages = rdbSavedObjectPages(val); +static int vmSwapObjectBlocking(robj *key, robj *val) { + off_t pages = rdbSavedObjectPages(val,NULL); off_t page; assert(key->storage == REDIS_VM_MEMORY); + assert(key->refcount == 1); if (vmFindContiguousPages(&page,pages) == REDIS_ERR) return REDIS_ERR; - if (fseeko(server.vm_fp,page*server.vm_page_size,SEEK_SET) == -1) { - redisLog(REDIS_WARNING, - "Critical VM problem in vmSwapObject(): can't seek: %s", - strerror(errno)); - return REDIS_ERR; - } - rdbSaveObject(server.vm_fp,val); + if (vmWriteObjectOnSwap(val,page) == REDIS_ERR) return REDIS_ERR; key->vm.page = page; key->vm.usedpages = pages; key->storage = REDIS_VM_SWAPPED; + key->vtype = val->type; decrRefCount(val); /* Deallocate the object from memory. */ vmMarkPagesUsed(page,pages); + redisLog(REDIS_DEBUG,"VM: object %s swapped out at %lld (%lld pages)", + (unsigned char*) key->ptr, + (unsigned long long) page, (unsigned long long) pages); + server.vm_stats_swapped_objects++; + server.vm_stats_swapouts++; + fflush(server.vm_fp); return REDIS_OK; } -/* Load the value object relative to the 'key' object from swap to memory. - * The newly allocated object is returned. */ -static robj *vmLoadObject(robj *key) { - robj *val; +static robj *vmReadObjectFromSwap(off_t page, int type) { + robj *o; - assert(key->storage == REDIS_VM_SWAPPED); - if (fseeko(server.vm_fp,key->vm.page*server.vm_page_size,SEEK_SET) == -1) { + if (server.vm_enabled) pthread_mutex_lock(&server.io_swapfile_mutex); + if (fseeko(server.vm_fp,page*server.vm_page_size,SEEK_SET) == -1) { redisLog(REDIS_WARNING, "Unrecoverable VM problem in vmLoadObject(): can't seek: %s", strerror(errno)); exit(1); } - val = rdbLoadObject(key->type,server.vm_fp); - if (val == NULL) { + o = rdbLoadObject(type,server.vm_fp); + if (o == NULL) { redisLog(REDIS_WARNING, "Unrecoverable VM problem in vmLoadObject(): can't load object from swap file: %s", strerror(errno)); exit(1); } - key->storage = REDIS_VM_MEMORY; - key->vm.atime = server.unixtime; - vmMarkPagesFree(key->vm.page,key->vm.usedpages); + if (server.vm_enabled) pthread_mutex_unlock(&server.io_swapfile_mutex); + return o; +} + +/* Load the value object relative to the 'key' object from swap to memory. + * The newly allocated object is returned. + * + * If preview is true the unserialized object is returned to the caller but + * no changes are made to the key object, nor the pages are marked as freed */ +static robj *vmGenericLoadObject(robj *key, int preview) { + robj *val; + + redisAssert(key->storage == REDIS_VM_SWAPPED); + val = vmReadObjectFromSwap(key->vm.page,key->vtype); + if (!preview) { + key->storage = REDIS_VM_MEMORY; + key->vm.atime = server.unixtime; + vmMarkPagesFree(key->vm.page,key->vm.usedpages); + redisLog(REDIS_DEBUG, "VM: object %s loaded from disk", + (unsigned char*) key->ptr); + server.vm_stats_swapped_objects--; + } else { + redisLog(REDIS_DEBUG, "VM: object %s previewed from disk", + (unsigned char*) key->ptr); + } + server.vm_stats_swapins++; return val; } +/* Plain object loading, from swap to memory */ +static robj *vmLoadObject(robj *key) { + /* If we are loading the object in background, stop it, we + * need to load this object synchronously ASAP. */ + if (key->storage == REDIS_VM_LOADING) + vmCancelThreadedIOJob(key); + return vmGenericLoadObject(key,0); +} + +/* Just load the value on disk, without to modify the key. + * This is useful when we want to perform some operation on the value + * without to really bring it from swap to memory, like while saving the + * dataset or rewriting the append only log. */ +static robj *vmPreviewObject(robj *key) { + return vmGenericLoadObject(key,1); +} + +/* How a good candidate is this object for swapping? + * The better candidate it is, the greater the returned value. + * + * Currently we try to perform a fast estimation of the object size in + * memory, and combine it with aging informations. + * + * Basically swappability = idle-time * log(estimated size) + * + * Bigger objects are preferred over smaller objects, but not + * proportionally, this is why we use the logarithm. This algorithm is + * just a first try and will probably be tuned later. */ +static double computeObjectSwappability(robj *o) { + time_t age = server.unixtime - o->vm.atime; + long asize = 0; + list *l; + dict *d; + struct dictEntry *de; + int z; + + if (age <= 0) return 0; + switch(o->type) { + case REDIS_STRING: + if (o->encoding != REDIS_ENCODING_RAW) { + asize = sizeof(*o); + } else { + asize = sdslen(o->ptr)+sizeof(*o)+sizeof(long)*2; + } + break; + case REDIS_LIST: + l = o->ptr; + listNode *ln = listFirst(l); + + asize = sizeof(list); + if (ln) { + robj *ele = ln->value; + long elesize; + + elesize = (ele->encoding == REDIS_ENCODING_RAW) ? + (sizeof(*o)+sdslen(ele->ptr)) : + sizeof(*o); + asize += (sizeof(listNode)+elesize)*listLength(l); + } + break; + case REDIS_SET: + case REDIS_ZSET: + z = (o->type == REDIS_ZSET); + d = z ? ((zset*)o->ptr)->dict : o->ptr; + + asize = sizeof(dict)+(sizeof(struct dictEntry*)*dictSlots(d)); + if (z) asize += sizeof(zset)-sizeof(dict); + if (dictSize(d)) { + long elesize; + robj *ele; + + de = dictGetRandomKey(d); + ele = dictGetEntryKey(de); + elesize = (ele->encoding == REDIS_ENCODING_RAW) ? + (sizeof(*o)+sdslen(ele->ptr)) : + sizeof(*o); + asize += (sizeof(struct dictEntry)+elesize)*dictSize(d); + if (z) asize += sizeof(zskiplistNode)*dictSize(d); + } + break; + } + return (double)asize*log(1+asize); +} + +/* Try to swap an object that's a good candidate for swapping. + * Returns REDIS_OK if the object was swapped, REDIS_ERR if it's not possible + * to swap any object at all. + * + * If 'usethreaded' is true, Redis will try to swap the object in background + * using I/O threads. */ +static int vmSwapOneObject(int usethreads) { + int j, i; + struct dictEntry *best = NULL; + double best_swappability = 0; + redisDb *best_db = NULL; + robj *key, *val; + + for (j = 0; j < server.dbnum; j++) { + redisDb *db = server.db+j; + int maxtries = 1000; + + if (dictSize(db->dict) == 0) continue; + for (i = 0; i < 5; i++) { + dictEntry *de; + double swappability; + + if (maxtries) maxtries--; + de = dictGetRandomKey(db->dict); + key = dictGetEntryKey(de); + val = dictGetEntryVal(de); + if (key->storage != REDIS_VM_MEMORY) { + if (maxtries) i--; /* don't count this try */ + continue; + } + swappability = computeObjectSwappability(val); + if (!best || swappability > best_swappability) { + best = de; + best_swappability = swappability; + best_db = db; + } + } + } + if (best == NULL) { + redisLog(REDIS_DEBUG,"No swappable key found!"); + return REDIS_ERR; + } + key = dictGetEntryKey(best); + val = dictGetEntryVal(best); + + redisLog(REDIS_DEBUG,"Key with best swappability: %s, %f", + key->ptr, best_swappability); + + /* Unshare the key if needed */ + if (key->refcount > 1) { + robj *newkey = dupStringObject(key); + decrRefCount(key); + key = dictGetEntryKey(best) = newkey; + } + /* Swap it */ + if (usethreads) { + vmSwapObjectThreaded(key,val,best_db); + return REDIS_OK; + } else { + if (vmSwapObjectBlocking(key,val) == REDIS_OK) { + dictGetEntryVal(best) = NULL; + return REDIS_OK; + } else { + return REDIS_ERR; + } + } +} + +static int vmSwapOneObjectBlocking() { + return vmSwapOneObject(0); +} + +static int vmSwapOneObjectThreaded() { + return vmSwapOneObject(1); +} + +/* Return true if it's safe to swap out objects in a given moment. + * Basically we don't want to swap objects out while there is a BGSAVE + * or a BGAEOREWRITE running in backgroud. */ +static int vmCanSwapOut(void) { + return (server.bgsavechildpid == -1 && server.bgrewritechildpid == -1); +} + +/* Delete a key if swapped. Returns 1 if the key was found, was swapped + * and was deleted. Otherwise 0 is returned. */ +static int deleteIfSwapped(redisDb *db, robj *key) { + dictEntry *de; + robj *foundkey; + + if ((de = dictFind(db->dict,key)) == NULL) return 0; + foundkey = dictGetEntryKey(de); + if (foundkey->storage == REDIS_VM_MEMORY) return 0; + deleteKey(db,key); + return 1; +} + +/* =================== Virtual Memory - Threaded I/O ======================= */ + +static void freeIOJob(iojob *j) { + if (j->type == REDIS_IOJOB_PREPARE_SWAP || + j->type == REDIS_IOJOB_DO_SWAP) + decrRefCount(j->val); + decrRefCount(j->key); + zfree(j); +} + +/* Every time a thread finished a Job, it writes a byte into the write side + * of an unix pipe in order to "awake" the main thread, and this function + * is called. */ +static void vmThreadedIOCompletedJob(aeEventLoop *el, int fd, void *privdata, + int mask) +{ + char buf[1]; + int retval; + int processed = 0; + REDIS_NOTUSED(el); + REDIS_NOTUSED(mask); + REDIS_NOTUSED(privdata); + + /* For every byte we read in the read side of the pipe, there is one + * I/O job completed to process. */ + while((retval = read(fd,buf,1)) == 1) { + iojob *j; + listNode *ln; + robj *key; + struct dictEntry *de; + + redisLog(REDIS_DEBUG,"Processing I/O completed job"); + assert(listLength(server.io_processed) != 0); + + /* Get the processed element (the oldest one) */ + lockThreadedIO(); + ln = listFirst(server.io_processed); + j = ln->value; + listDelNode(server.io_processed,ln); + unlockThreadedIO(); + /* If this job is marked as canceled, just ignore it */ + if (j->canceled) { + freeIOJob(j); + continue; + } + /* Post process it in the main thread, as there are things we + * can do just here to avoid race conditions and/or invasive locks */ + redisLog(REDIS_DEBUG,"Job %p type: %d, key at %p (%s) refcount: %d\n", (void*) j, j->type, (void*)j->key, (char*)j->key->ptr, j->key->refcount); + de = dictFind(j->db->dict,j->key); + assert(de != NULL); + key = dictGetEntryKey(de); + if (j->type == REDIS_IOJOB_LOAD) { + /* Key loaded, bring it at home */ + key->storage = REDIS_VM_MEMORY; + key->vm.atime = server.unixtime; + vmMarkPagesFree(key->vm.page,key->vm.usedpages); + redisLog(REDIS_DEBUG, "VM: object %s loaded from disk (threaded)", + (unsigned char*) key->ptr); + server.vm_stats_swapped_objects--; + server.vm_stats_swapins++; + freeIOJob(j); + } else if (j->type == REDIS_IOJOB_PREPARE_SWAP) { + /* Now we know the amount of pages required to swap this object. + * Let's find some space for it, and queue this task again + * rebranded as REDIS_IOJOB_DO_SWAP. */ + if (vmFindContiguousPages(&j->page,j->pages) == REDIS_ERR) { + /* Ooops... no space! */ + freeIOJob(j); + } else { + /* Note that we need to mark this pages as used now, + * if the job will be canceled, we'll mark them as freed + * again. */ + vmMarkPagesUsed(j->page,j->pages); + j->type = REDIS_IOJOB_DO_SWAP; + lockThreadedIO(); + queueIOJob(j); + unlockThreadedIO(); + } + } else if (j->type == REDIS_IOJOB_DO_SWAP) { + robj *val; + + /* Key swapped. We can finally free some memory. */ + if (key->storage != REDIS_VM_SWAPPING) { + printf("key->storage: %d\n",key->storage); + printf("key->name: %s\n",(char*)key->ptr); + printf("key->refcount: %d\n",key->refcount); + printf("val: %p\n",(void*)j->val); + printf("val->type: %d\n",j->val->type); + printf("val->ptr: %s\n",(char*)j->val->ptr); + } + redisAssert(key->storage == REDIS_VM_SWAPPING); + val = dictGetEntryVal(de); + key->vm.page = j->page; + key->vm.usedpages = j->pages; + key->storage = REDIS_VM_SWAPPED; + key->vtype = j->val->type; + decrRefCount(val); /* Deallocate the object from memory. */ + dictGetEntryVal(de) = NULL; + redisLog(REDIS_DEBUG, + "VM: object %s swapped out at %lld (%lld pages) (threaded)", + (unsigned char*) key->ptr, + (unsigned long long) j->page, (unsigned long long) j->pages); + server.vm_stats_swapped_objects++; + server.vm_stats_swapouts++; + freeIOJob(j); + /* Put a few more swap requests in queue if we are still + * out of memory */ + if (zmalloc_used_memory() > server.vm_max_memory) { + int more = 1; + while(more) { + lockThreadedIO(); + more = listLength(server.io_newjobs) < + (unsigned) server.vm_max_threads; + unlockThreadedIO(); + /* Don't waste CPU time if swappable objects are rare. */ + if (vmSwapOneObjectThreaded() == REDIS_ERR) break; + } + } + } + processed++; + if (processed == REDIS_MAX_COMPLETED_JOBS_PROCESSED) return; + } + if (retval < 0 && errno != EAGAIN) { + redisLog(REDIS_WARNING, + "WARNING: read(2) error in vmThreadedIOCompletedJob() %s", + strerror(errno)); + } +} + +static void lockThreadedIO(void) { + pthread_mutex_lock(&server.io_mutex); +} + +static void unlockThreadedIO(void) { + pthread_mutex_unlock(&server.io_mutex); +} + +/* Remove the specified object from the threaded I/O queue if still not + * processed, otherwise make sure to flag it as canceled. */ +static void vmCancelThreadedIOJob(robj *o) { + list *lists[3] = { + server.io_newjobs, /* 0 */ + server.io_processing, /* 1 */ + server.io_processed /* 2 */ + }; + int i; + + assert(o->storage == REDIS_VM_LOADING || o->storage == REDIS_VM_SWAPPING); + lockThreadedIO(); + /* Search for a matching key in one of the queues */ + for (i = 0; i < 3; i++) { + listNode *ln; + listIter li; + + listRewind(lists[i],&li); + while ((ln = listNext(&li)) != NULL) { + iojob *job = ln->value; + + if (job->canceled) continue; /* Skip this, already canceled. */ + if (compareStringObjects(job->key,o) == 0) { + redisLog(REDIS_DEBUG,"*** CANCELED %p (%s)\n", + (void*)job, (char*)o->ptr); + /* Mark the pages as free since the swap didn't happened + * or happened but is now discarded. */ + if (job->type == REDIS_IOJOB_DO_SWAP) + vmMarkPagesFree(job->page,job->pages); + /* Cancel the job. It depends on the list the job is + * living in. */ + switch(i) { + case 0: /* io_newjobs */ + /* If the job was yet not processed the best thing to do + * is to remove it from the queue at all */ + freeIOJob(job); + listDelNode(lists[i],ln); + break; + case 1: /* io_processing */ + case 2: /* io_processed */ + job->canceled = 1; + break; + } + /* Finally we have to adjust the storage type of the object + * in order to "UNDO" the operaiton. */ + if (o->storage == REDIS_VM_LOADING) + o->storage = REDIS_VM_SWAPPED; + else if (o->storage == REDIS_VM_SWAPPING) + o->storage = REDIS_VM_MEMORY; + unlockThreadedIO(); + return; + } + } + } + unlockThreadedIO(); + assert(1 != 1); /* We should never reach this */ +} + +static void *IOThreadEntryPoint(void *arg) { + iojob *j; + listNode *ln; + REDIS_NOTUSED(arg); + + pthread_detach(pthread_self()); + while(1) { + /* Get a new job to process */ + lockThreadedIO(); + if (listLength(server.io_newjobs) == 0) { + /* No new jobs in queue, exit. */ + redisLog(REDIS_DEBUG,"Thread %lld exiting, nothing to do", + (long long) pthread_self()); + server.io_active_threads--; + unlockThreadedIO(); + return NULL; + } + ln = listFirst(server.io_newjobs); + j = ln->value; + listDelNode(server.io_newjobs,ln); + /* Add the job in the processing queue */ + j->thread = pthread_self(); + listAddNodeTail(server.io_processing,j); + ln = listLast(server.io_processing); /* We use ln later to remove it */ + unlockThreadedIO(); + redisLog(REDIS_DEBUG,"Thread %lld got a new job (type %d): %p about key '%s'", + (long long) pthread_self(), j->type, (void*)j, (char*)j->key->ptr); + + /* Process the Job */ + if (j->type == REDIS_IOJOB_LOAD) { + } else if (j->type == REDIS_IOJOB_PREPARE_SWAP) { + FILE *fp = fopen("/dev/null","w+"); + j->pages = rdbSavedObjectPages(j->val,fp); + fclose(fp); + } else if (j->type == REDIS_IOJOB_DO_SWAP) { + if (vmWriteObjectOnSwap(j->val,j->page) == REDIS_ERR) + j->canceled = 1; + } + + /* Done: insert the job into the processed queue */ + redisLog(REDIS_DEBUG,"Thread %lld completed the job: %p (key %s)", + (long long) pthread_self(), (void*)j, (char*)j->key->ptr); + lockThreadedIO(); + listDelNode(server.io_processing,ln); + listAddNodeTail(server.io_processed,j); + unlockThreadedIO(); + + /* Signal the main thread there is new stuff to process */ + assert(write(server.io_ready_pipe_write,"x",1) == 1); + } + return NULL; /* never reached */ +} + +static void spawnIOThread(void) { + pthread_t thread; + + pthread_create(&thread,&server.io_threads_attr,IOThreadEntryPoint,NULL); + server.io_active_threads++; +} + +/* We need to wait for the last thread to exit before we are able to + * fork() in order to BGSAVE or BGREWRITEAOF. */ +static void waitZeroActiveThreads(void) { + while(1) { + lockThreadedIO(); + if (server.io_active_threads == 0) { + unlockThreadedIO(); + return; + } + unlockThreadedIO(); + usleep(10000); /* 10 milliseconds */ + } +} + +/* This function must be called while with threaded IO locked */ +static void queueIOJob(iojob *j) { + redisLog(REDIS_DEBUG,"Queued IO Job %p type %d about key '%s'\n", + (void*)j, j->type, (char*)j->key->ptr); + listAddNodeTail(server.io_newjobs,j); + if (server.io_active_threads < server.vm_max_threads) + spawnIOThread(); +} + +static int vmSwapObjectThreaded(robj *key, robj *val, redisDb *db) { + iojob *j; + + assert(key->storage == REDIS_VM_MEMORY); + assert(key->refcount == 1); + + j = zmalloc(sizeof(*j)); + j->type = REDIS_IOJOB_PREPARE_SWAP; + j->db = db; + j->key = dupStringObject(key); + j->val = val; + incrRefCount(val); + j->canceled = 0; + j->thread = (pthread_t) -1; + key->storage = REDIS_VM_SWAPPING; + + lockThreadedIO(); + queueIOJob(j); + unlockThreadedIO(); + return REDIS_OK; +} + /* ================================= Debugging ============================== */ static void debugCommand(redisClient *c) { @@ -6833,19 +7760,58 @@ static void debugCommand(redisClient *c) { } key = dictGetEntryKey(de); val = dictGetEntryVal(de); - addReplySds(c,sdscatprintf(sdsempty(), - "+Key at:%p refcount:%d, value at:%p refcount:%d encoding:%d serializedlength:%lld\r\n", + if (server.vm_enabled && (key->storage == REDIS_VM_MEMORY || + key->storage == REDIS_VM_SWAPPING)) { + addReplySds(c,sdscatprintf(sdsempty(), + "+Key at:%p refcount:%d, value at:%p refcount:%d " + "encoding:%d serializedlength:%lld\r\n", (void*)key, key->refcount, (void*)val, val->refcount, - val->encoding, rdbSavedObjectLen(val))); + val->encoding, rdbSavedObjectLen(val,NULL))); + } else { + addReplySds(c,sdscatprintf(sdsempty(), + "+Key at:%p refcount:%d, value swapped at: page %llu " + "using %llu pages\r\n", + (void*)key, key->refcount, (unsigned long long) key->vm.page, + (unsigned long long) key->vm.usedpages)); + } + } else if (!strcasecmp(c->argv[1]->ptr,"swapout") && c->argc == 3) { + dictEntry *de = dictFind(c->db->dict,c->argv[2]); + robj *key, *val; + + if (!server.vm_enabled) { + addReplySds(c,sdsnew("-ERR Virtual Memory is disabled\r\n")); + return; + } + if (!de) { + addReply(c,shared.nokeyerr); + return; + } + key = dictGetEntryKey(de); + val = dictGetEntryVal(de); + /* If the key is shared we want to create a copy */ + if (key->refcount > 1) { + robj *newkey = dupStringObject(key); + decrRefCount(key); + key = dictGetEntryKey(de) = newkey; + } + /* Swap it */ + if (key->storage != REDIS_VM_MEMORY) { + addReplySds(c,sdsnew("-ERR This key is not in memory\r\n")); + } else if (vmSwapObjectBlocking(key,val) == REDIS_OK) { + dictGetEntryVal(de) = NULL; + addReply(c,shared.ok); + } else { + addReply(c,shared.err); + } } else { addReplySds(c,sdsnew( - "-ERR Syntax error, try DEBUG [SEGFAULT|OBJECT |RELOAD]\r\n")); + "-ERR Syntax error, try DEBUG [SEGFAULT|OBJECT |SWAPOUT |RELOAD]\r\n")); } } -static void _redisAssert(char *estr) { +static void _redisAssert(char *estr, char *file, int line) { redisLog(REDIS_WARNING,"=== ASSERTION FAILED ==="); - redisLog(REDIS_WARNING,"==> %s\n",estr); + redisLog(REDIS_WARNING,"==> %s:%d '%s' is not true\n",file,line,estr); #ifdef HAVE_BACKTRACE redisLog(REDIS_WARNING,"(forcing SIGSEGV in order to print the stack trace)"); *((char*)-1) = 'x'; @@ -6881,7 +7847,6 @@ static void daemonize(void) { FILE *fp; if (fork() != 0) exit(0); /* parent exits */ - printf("New pid: %d\n", getpid()); setsid(); /* create a new session */ /* Every output goes to /dev/null. If Redis is daemonized but @@ -6925,8 +7890,6 @@ int main(int argc, char **argv) { if (rdbLoad(server.dbfilename) == REDIS_OK) redisLog(REDIS_NOTICE,"DB loaded from disk"); } - if (aeCreateFileEvent(server.el, server.fd, AE_READABLE, - acceptHandler, NULL) == AE_ERR) oom("creating file event"); redisLog(REDIS_NOTICE,"The server is now ready to accept connections on port %d", server.port); aeMain(server.el); aeDeleteEventLoop(server.el);