Merge commit 'df83892760d19b1b7e92d76e72daf4834ad2df6c' into redis_6_merge

Former-commit-id: cde199a7973ad63317b68f581df607321e12bf46

README.md

@@ -88,6 +88,11 @@ Compiling is as simple as:
 
     % make
 
+To build with TLS support, you'll need OpenSSL development libraries (e.g.
+libssl-dev on Debian/Ubuntu) and run:
+
+    % make BUILD_TLS=yes
+
 You can enable flash support with:
 
     % make MALLOC=memkind
@@ -95,6 +100,13 @@ You can enable flash support with:
 ***Note that the following dependencies may be needed: 
     % sudo apt-get install autoconf autotools-dev libnuma-dev libtool
 
+If TLS is built, running the tests with TLS enabled (you will need `tcl-tls`
+installed):
+
+    % ./utils/gen-test-certs.sh
+    % ./runtest --tls
+
+
 Fixing build problems with dependencies or cached build options
 ---------
 
@@ -177,6 +189,14 @@ as options using the command line. Examples:
 All the options in keydb.conf are also supported as options using the command
 line, with exactly the same name.
 
+
+Running Redis with TLS:
+------------------
+
+Please consult the [TLS.md](TLS.md) file for more information on
+how to use Redis with TLS.
+
+
 Playing with KeyDB
 ------------------
 
@@ -253,49 +273,8 @@ $ docker run -it --rm -v /path-to-dump-binaries:/keydb_bin eqalpha/keydb-build-b
 ```
 Please note that you will need libcurl4-openssl-dev in order to run keydb. With flash version you may need libnuma-dev and libtool installed in order to run the binaries. Keep this in mind especially when running in a container. For a copy of all our Dockerfiles, please see them on [docs]( https://docs.keydb.dev/docs/dockerfiles/).
 
-<<<<<<< HEAD
 Code contributions
 -----------------
-=======
-One of the most important functions inside this file is `replicationFeedSlaves()` that writes commands to the clients representing replica instances connected
-to our master, so that the replicas can get the writes performed by the clients:
-this way their data set will remain synchronized with the one in the master.
-
-This file also implements both the `SYNC` and `PSYNC` commands that are
-used in order to perform the first synchronization between masters and
-replicas, or to continue the replication after a disconnection.
-
-Other C files
----
-
-* `t_hash.c`, `t_list.c`, `t_set.c`, `t_string.c`, `t_zset.c` and `t_stream.c` contains the implementation of the Redis data types. They implement both an API to access a given data type, and the client commands implementations for these data types.
-* `ae.c` implements the Redis event loop, it's a self contained library which is simple to read and understand.
-* `sds.c` is the Redis string library, check http://github.com/antirez/sds for more information.
-* `anet.c` is a library to use POSIX networking in a simpler way compared to the raw interface exposed by the kernel.
-* `dict.c` is an implementation of a non-blocking hash table which rehashes incrementally.
-* `scripting.c` implements Lua scripting. It is completely self contained from the rest of the Redis implementation and is simple enough to understand if you are familar with the Lua API.
-* `cluster.c` implements the Redis Cluster. Probably a good read only after being very familiar with the rest of the Redis code base. If you want to read `cluster.c` make sure to read the [Redis Cluster specification][3].
-
-[3]: http://redis.io/topics/cluster-spec
-
-Anatomy of a Redis command
----
-
-All the Redis commands are defined in the following way:
-
-    void foobarCommand(client *c) {
-        printf("%s",c->argv[1]->ptr); /* Do something with the argument. */
-        addReply(c,shared.ok); /* Reply something to the client. */
-    }
-
-The command is then referenced inside `server.c` in the command table:
-
-    {"foobar",foobarCommand,2,"rtF",0,NULL,0,0,0,0,0},
-
-In the above example `2` is the number of arguments the command takes,
-while `"rtF"` are the command flags, as documented in the command table
-top comment inside `server.c`.
->>>>>>> redis/6.0
 
 Note: by contributing code to the KeyDB project in any form, including sending
 a pull request via Github, a code fragment or patch via private email or

TLS.md

@@ -1,8 +1,5 @@
-TLS Support -- Work In Progress
+TLS Support
-===============================
+===========
-
-This is a brief note to capture current thoughts/ideas and track pending action
-items.
 
 Getting Started
 ---------------
@@ -69,37 +66,23 @@ probably not be so hard. For cluster keys migration it might be more difficult,
 but there are probably other good reasons to improve that part anyway.
 
 To-Do List
-==========
+----------
 
-Additional TLS Features
+- [ ] Add session caching support. Check if/how it's handled by clients to
------------------------
+  assess how useful/important it is.
+- [ ] redis-benchmark support. The current implementation is a mix of using
+  hiredis for parsing and basic networking (establishing connections), but
+  directly manipulating sockets for most actions. This will need to be cleaned
+  up for proper TLS support. The best approach is probably to migrate to hiredis
+  async mode.
+- [ ] redis-cli `--slave` and `--rdb` support.
 
-1. Add metrics to INFO?
+Multi-port
-2. Add session caching support. Check if/how it's handled by clients to assess
+----------
-   how useful/important it is.
-
-redis-benchmark
----------------
-
-The current implementation is a mix of using hiredis for parsing and basic
-networking (establishing connections), but directly manipulating sockets for
-most actions.
-
-This will need to be cleaned up for proper TLS support. The best approach is
-probably to migrate to hiredis async mode.
-
-redis-cli
----------
-
-1. Add support for TLS in --slave and --rdb modes.
-
-Others
-------
 
 Consider the implications of allowing TLS to be configured on a separate port,
-making Redis listening on multiple ports.
+making Redis listening on multiple ports:
 
-This impacts many things, like
 1. Startup banner port notification
 2. Proctitle
 3. How slaves announce themselves

deps/lua/src/lua_struct.c

@@ -89,12 +89,14 @@ typedef struct Header {
 } Header;
 
 
-static int getnum (const char **fmt, int df) {
+static int getnum (lua_State *L, const char **fmt, int df) {
   if (!isdigit(**fmt))  /* no number? */
     return df;  /* return default value */
   else {
     int a = 0;
     do {
+      if (a > (INT_MAX / 10) || a * 10 > (INT_MAX - (**fmt - '0')))
+        luaL_error(L, "integral size overflow");
       a = a*10 + *((*fmt)++) - '0';
     } while (isdigit(**fmt));
     return a;
@@ -115,9 +117,9 @@ static size_t optsize (lua_State *L, char opt, const char **fmt) {
     case 'f':  return sizeof(float);
     case 'd':  return sizeof(double);
     case 'x': return 1;
-    case 'c': return getnum(fmt, 1);
+    case 'c': return getnum(L, fmt, 1);
     case 'i': case 'I': {
-      int sz = getnum(fmt, sizeof(int));
+      int sz = getnum(L, fmt, sizeof(int));
       if (sz > MAXINTSIZE)
         luaL_error(L, "integral size %d is larger than limit of %d",
                        sz, MAXINTSIZE);
@@ -150,7 +152,7 @@ static void controloptions (lua_State *L, int opt, const char **fmt,
     case '>': h->endian = BIG; return;
     case '<': h->endian = LITTLE; return;
     case '!': {
-      int a = getnum(fmt, MAXALIGN);
+      int a = getnum(L, fmt, MAXALIGN);
       if (!isp2(a))
         luaL_error(L, "alignment %d is not a power of 2", a);
       h->align = a;

keydb.conf

@@ -1361,7 +1361,11 @@ latency-monitor-threshold 0
 #  z     Sorted set commands
 #  x     Expired events (events generated every time a key expires)
 #  e     Evicted events (events generated when a key is evicted for maxmemory)
-#  A     Alias for g$lshzxe, so that the "AKE" string means all the events.
+#  t     Stream commands
+#  m     Key-miss events (Note: It is not included in the 'A' class)
+#  A     Alias for g$lshzxet, so that the "AKE" string means all the events
+#        (Except key-miss events which are excluded from 'A' due to their
+#         unique nature).
 #
 #  The "notify-keyspace-events" takes as argument a string that is composed
 #  of zero or multiple characters. The empty string means that notifications

src/config.cpp

@@ -358,6 +358,10 @@ void loadServerConfigFromString(char *config) {
             if (addresses > CONFIG_BINDADDR_MAX) {
                 err = "Too many bind addresses specified"; goto loaderr;
             }
+            /* Free old bind addresses */
+            for (j = 0; j < g_pserver->bindaddr_count; j++) {
+                zfree(g_pserver->bindaddr[j]);
+            }
             for (j = 0; j < addresses; j++)
                 g_pserver->bindaddr[j] = zstrdup(argv[j+1]);
             g_pserver->bindaddr_count = addresses;
@@ -2083,8 +2087,9 @@ static int updateMaxmemory(long long val, long long prev, const char **err) {
     UNUSED(prev);
     UNUSED(err);
     if (val) {
-        if ((unsigned long long)val < zmalloc_used_memory()) {
+        size_t used = zmalloc_used_memory()-freeMemoryGetNotCountedMemory();
-            serverLog(LL_WARNING,"WARNING: the new maxmemory value set via CONFIG SET is smaller than the current memory usage. This will result in key eviction and/or the inability to accept new write commands depending on the maxmemory-policy.");
+        if ((unsigned long long)val < used) {
+            serverLog(LL_WARNING,"WARNING: the new maxmemory value set via CONFIG SET (%llu) is smaller than the current memory usage (%zu). This will result in key eviction and/or the inability to accept new write commands depending on the maxmemory-policy.", g_pserver->maxmemory, used);
         }
         freeMemoryIfNeededAndSafe();
     }

src/module.cpp

@@ -728,9 +728,9 @@ void RM_KeyAtPos(RedisModuleCtx *ctx, int pos) {
  * flags into the command flags used by the Redis core.
  *
  * It returns the set of flags, or -1 if unknown flags are found. */
-int commandFlagsFromString(char *s) {
+int64_t commandFlagsFromString(char *s) {
     int count, j;
-    int flags = 0;
+    int64_t flags = 0;
     sds *tokens = sdssplitlen(s,strlen(s)," ",1,&count);
     for (j = 0; j < count; j++) {
         char *t = tokens[j];
@@ -744,6 +744,7 @@ int commandFlagsFromString(char *s) {
         else if (!strcasecmp(t,"random")) flags |= CMD_RANDOM;
         else if (!strcasecmp(t,"allow-stale")) flags |= CMD_STALE;
         else if (!strcasecmp(t,"no-monitor")) flags |= CMD_SKIP_MONITOR;
+        else if (!strcasecmp(t,"no-slowlog")) flags |= CMD_SKIP_SLOWLOG;
         else if (!strcasecmp(t,"fast")) flags |= CMD_FAST;
         else if (!strcasecmp(t,"no-auth")) flags |= CMD_NO_AUTH;
         else if (!strcasecmp(t,"getkeys-api")) flags |= CMD_MODULE_GETKEYS;
@@ -795,6 +796,8 @@ int commandFlagsFromString(char *s) {
  *                      this means.
  * * **"no-monitor"**: Don't propagate the command on monitor. Use this if
  *                     the command has sensible data among the arguments.
+ * * **"no-slowlog"**: Don't log this command in the slowlog. Use this if
+ *                     the command has sensible data among the arguments.
  * * **"fast"**:      The command time complexity is not greater
  *                    than O(log(N)) where N is the size of the collection or
  *                    anything else representing the normal scalability
@@ -812,7 +815,7 @@ int commandFlagsFromString(char *s) {
  *                     to authenticate a client. 
  */
 int RM_CreateCommand(RedisModuleCtx *ctx, const char *name, RedisModuleCmdFunc cmdfunc, const char *strflags, int firstkey, int lastkey, int keystep) {
-    int flags = strflags ? commandFlagsFromString((char*)strflags) : 0;
+    int64_t flags = strflags ? commandFlagsFromString((char*)strflags) : 0;
     if (flags == -1) return REDISMODULE_ERR;
     if ((flags & CMD_MODULE_NO_CLUSTER) && g_pserver->cluster_enabled)
         return REDISMODULE_ERR;
@@ -904,7 +907,8 @@ void RM_SetModuleOptions(RedisModuleCtx *ctx, int options) {
     ctx->module->options = options;
 }
 
-/* Signals that the key is modified from user's perspective (i.e. invalidate WATCH). */
+/* Signals that the key is modified from user's perspective (i.e. invalidate WATCH
+ * and client side caching). */
 int RM_SignalModifiedKey(RedisModuleCtx *ctx, RedisModuleString *keyname) {
     signalModifiedKey(ctx->client->db,keyname);
     return REDISMODULE_OK;
@@ -3725,14 +3729,15 @@ void moduleRDBLoadError(RedisModuleIO *io) {
         io->error = 1;
         return;
     }
-    serverLog(LL_WARNING,
+    serverPanic(
         "Error loading data from RDB (short read or EOF). "
         "Read performed by module '%s' about type '%s' "
-        "after reading '%llu' bytes of a value.",
+        "after reading '%llu' bytes of a value "
+        "for key named: '%s'.",
         io->type->module->name,
         io->type->name,
-        (unsigned long long)io->bytes);
+        (unsigned long long)io->bytes,
-    exit(1);
+        io->key? szFromObj(io->key): "(null)");
 }
 
 /* Returns 0 if there's at least one registered data type that did not declare
@@ -4934,7 +4939,8 @@ int moduleGILAcquiredByModule(void) {
  *  - REDISMODULE_NOTIFY_EXPIRED: Expiration events
  *  - REDISMODULE_NOTIFY_EVICTED: Eviction events
  *  - REDISMODULE_NOTIFY_STREAM: Stream events
- *  - REDISMODULE_NOTIFY_ALL: All events
+ *  - REDISMODULE_NOTIFY_KEYMISS: Key-miss events
+ *  - REDISMODULE_NOTIFY_ALL: All events (Excluding REDISMODULE_NOTIFY_KEYMISS)
  *
  * We do not distinguish between key events and keyspace events, and it is up
  * to the module to filter the actions taken based on the key.

src/notify.cpp

@@ -82,10 +82,10 @@ sds keyspaceEventsFlagsToString(int flags) {
         if (flags & NOTIFY_EXPIRED) res = sdscatlen(res,"x",1);
         if (flags & NOTIFY_EVICTED) res = sdscatlen(res,"e",1);
         if (flags & NOTIFY_STREAM) res = sdscatlen(res,"t",1);
-        if (flags & NOTIFY_KEY_MISS) res = sdscatlen(res,"m",1);
     }
     if (flags & NOTIFY_KEYSPACE) res = sdscatlen(res,"K",1);
     if (flags & NOTIFY_KEYEVENT) res = sdscatlen(res,"E",1);
+    if (flags & NOTIFY_KEY_MISS) res = sdscatlen(res,"m",1);
     return res;
 }
 

src/rax.c

@@ -1766,6 +1766,7 @@ int raxRandomWalk(raxIterator *it, size_t steps) {
         if (n->iskey) steps--;
     }
     it->node = n;
+    it->data = raxGetData(it->node);
     return 1;
 }
 

src/rdb.cpp

@@ -1975,7 +1975,10 @@ robj *rdbLoadObject(int rdbtype, rio *rdb, robj *key, uint64_t mvcc_tstamp) {
         }
     } else if (rdbtype == RDB_TYPE_MODULE || rdbtype == RDB_TYPE_MODULE_2) {
         uint64_t moduleid = rdbLoadLen(rdb,NULL);
-        if (rioGetReadError(rdb)) return NULL;
+        if (rioGetReadError(rdb)) {
+            rdbReportReadError("Short read module id");
+            return NULL;
+        }
         moduleType *mt = moduleTypeLookupModuleByID(moduleid);
         char name[10];
 

src/redis-cli.c

@@ -1407,15 +1407,15 @@ static int parseOptions(int argc, char **argv) {
 #ifdef USE_OPENSSL
         } else if (!strcmp(argv[i],"--tls")) {
             config.tls = 1;
-        } else if (!strcmp(argv[i],"--sni")) {
+        } else if (!strcmp(argv[i],"--sni") && !lastarg) {
             config.sni = argv[++i];
-        } else if (!strcmp(argv[i],"--cacertdir")) {
+        } else if (!strcmp(argv[i],"--cacertdir") && !lastarg) {
             config.cacertdir = argv[++i];
-        } else if (!strcmp(argv[i],"--cacert")) {
+        } else if (!strcmp(argv[i],"--cacert") && !lastarg) {
             config.cacert = argv[++i];
-        } else if (!strcmp(argv[i],"--cert")) {
+        } else if (!strcmp(argv[i],"--cert") && !lastarg) {
             config.cert = argv[++i];
-        } else if (!strcmp(argv[i],"--key")) {
+        } else if (!strcmp(argv[i],"--key") && !lastarg) {
             config.key = argv[++i];
 #endif
         } else if (!strcmp(argv[i],"-v") || !strcmp(argv[i], "--version")) {
@@ -1500,8 +1500,8 @@ static void usage(void) {
 "                     You can also use the " REDIS_CLI_AUTH_ENV " environment\n"
 "                     variable to pass this password more safely\n"
 "                     (if both are used, this argument takes predecence).\n"
-"  -user <username>   Used to send ACL style 'AUTH username pass'. Needs -a.\n"
+"  --user <username>  Used to send ACL style 'AUTH username pass'. Needs -a.\n"
-"  -pass <password>   Alias of -a for consistency with the new --user option.\n"
+"  --pass <password>  Alias of -a for consistency with the new --user option.\n"
 "  -u <uri>           Server URI.\n"
 "  -r <repeat>        Execute specified command N times.\n"
 "  -i <interval>      When -r is used, waits <interval> seconds per command.\n"
@@ -1513,12 +1513,13 @@ static void usage(void) {
 "  -c                 Enable cluster mode (follow -ASK and -MOVED redirections).\n"
 #ifdef USE_OPENSSL
 "  --tls              Establish a secure TLS connection.\n"
-"  --cacert           CA Certificate file to verify with.\n"
+"  --sni <host>       Server name indication for TLS.\n"
-"  --cacertdir        Directory where trusted CA certificates are stored.\n"
+"  --cacert <file>    CA Certificate file to verify with.\n"
+"  --cacertdir <dir>  Directory where trusted CA certificates are stored.\n"
 "                     If neither cacert nor cacertdir are specified, the default\n"
 "                     system-wide trusted root certs configuration will apply.\n"
-"  --cert             Client certificate to authenticate with.\n"
+"  --cert <file>      Client certificate to authenticate with.\n"
-"  --key              Private key file to authenticate with.\n"
+"  --key <file>       Private key file to authenticate with.\n"
 #endif
 "  --raw              Use raw formatting for replies (default when STDOUT is\n"
 "                     not a tty).\n"

src/redismodule.h

@@ -131,8 +131,8 @@ extern "C" {
 #define REDISMODULE_NOTIFY_EXPIRED (1<<8)     /* x */
 #define REDISMODULE_NOTIFY_EVICTED (1<<9)     /* e */
 #define REDISMODULE_NOTIFY_STREAM (1<<10)     /* t */
-#define REDISMODULE_NOTIFY_KEY_MISS (1<<11)   /* m */
+#define REDISMODULE_NOTIFY_KEY_MISS (1<<11)   /* m (Note: This one is excluded from REDISMODULE_NOTIFY_ALL on purpose) */
-#define REDISMODULE_NOTIFY_ALL (REDISMODULE_NOTIFY_GENERIC | REDISMODULE_NOTIFY_STRING | REDISMODULE_NOTIFY_LIST | REDISMODULE_NOTIFY_SET | REDISMODULE_NOTIFY_HASH | REDISMODULE_NOTIFY_ZSET | REDISMODULE_NOTIFY_EXPIRED | REDISMODULE_NOTIFY_EVICTED | REDISMODULE_NOTIFY_STREAM | REDISMODULE_NOTIFY_KEY_MISS)      /* A */
+#define REDISMODULE_NOTIFY_ALL (REDISMODULE_NOTIFY_GENERIC | REDISMODULE_NOTIFY_STRING | REDISMODULE_NOTIFY_LIST | REDISMODULE_NOTIFY_SET | REDISMODULE_NOTIFY_HASH | REDISMODULE_NOTIFY_ZSET | REDISMODULE_NOTIFY_EXPIRED | REDISMODULE_NOTIFY_EVICTED | REDISMODULE_NOTIFY_STREAM)      /* A */
 
 
 /* A special pointer that we can use between the core and the module to signal

src/replication.cpp

@@ -2927,6 +2927,10 @@ void replicationUnsetMaster(redisMaster *mi) {
     moduleFireServerEvent(REDISMODULE_EVENT_REPLICATION_ROLE_CHANGED,
                           REDISMODULE_EVENT_REPLROLECHANGED_NOW_MASTER,
                           NULL);
+
+    /* Restart the AOF subsystem in case we shut it down during a sync when
+     * we were still a slave. */
+    if (g_pserver->aof_enabled && g_pserver->aof_state == AOF_OFF) restartAOFAfterSYNC();
 }
 
 /* This function is called when the replica lose the connection with the
@@ -2969,9 +2973,6 @@ void replicaofCommand(client *c) {
             serverLog(LL_NOTICE,"MASTER MODE enabled (user request from '%s')",
                 client);
             sdsfree(client);
-            /* Restart the AOF subsystem in case we shut it down during a sync when
-             * we were still a slave. */
-            if (g_pserver->aof_enabled && g_pserver->aof_state == AOF_OFF) restartAOFAfterSYNC();
         }
     } else {
         long port;

src/server.cpp

@@ -600,7 +600,7 @@ struct redisCommand redisCommandTable[] = {
      0,NULL,0,0,0,0,0,0},
 
     {"select",selectCommand,2,
-     "ok-loading fast @keyspace",
+     "ok-loading fast ok-stale @keyspace",
      0,NULL,0,0,0,0,0,0},
 
     {"swapdb",swapdbCommand,3,
@@ -689,7 +689,7 @@ struct redisCommand redisCommandTable[] = {
      0,NULL,0,0,0,0,0,0},
 
     {"lastsave",lastsaveCommand,1,
-     "read-only random fast @admin @dangerous",
+     "read-only random fast ok-loading ok-stale @admin @dangerous",
      0,NULL,0,0,0,0,0,0},
 
     {"type",typeCommand,2,
@@ -737,7 +737,7 @@ struct redisCommand redisCommandTable[] = {
      0,NULL,0,0,0,0,0,0},
 
     {"monitor",monitorCommand,1,
-     "admin no-script",
+     "admin no-script ok-loading ok-stale",
      0,NULL,0,0,0,0,0,0},
 
     {"ttl",ttlCommand,-2,
@@ -769,7 +769,7 @@ struct redisCommand redisCommandTable[] = {
      0,NULL,0,0,0,0,0,0},
 
     {"debug",debugCommand,-2,
-     "admin no-script",
+     "admin no-script ok-loading ok-stale",
      0,NULL,0,0,0,0,0,0},
 
     {"config",configCommand,-2,
@@ -849,11 +849,11 @@ struct redisCommand redisCommandTable[] = {
      0,memoryGetKeys,0,0,0,0,0,0},
 
     {"client",clientCommand,-2,
-     "admin no-script random @connection",
+     "admin no-script random ok-loading ok-stale @connection",
      0,NULL,0,0,0,0,0,0},
 
     {"hello",helloCommand,-2,
-     "no-auth no-script fast no-monitor no-slowlog @connection",
+     "no-auth no-script fast no-monitor ok-loading ok-stale no-slowlog @connection",
      0,NULL,0,0,0,0,0,0},
 
     /* EVAL can modify the dataset, however it is not flagged as a write
@@ -867,7 +867,7 @@ struct redisCommand redisCommandTable[] = {
      0,evalGetKeys,0,0,0,0,0,0},
 
     {"slowlog",slowlogCommand,-2,
-     "admin random",
+     "admin random ok-loading ok-stale",
      0,NULL,0,0,0,0,0,0},
 
     {"script",scriptCommand,-2,
@@ -875,7 +875,7 @@ struct redisCommand redisCommandTable[] = {
      0,NULL,0,0,0,0,0,0},
 
     {"time",timeCommand,1,
-     "read-only random fast",
+     "read-only random fast ok-loading ok-stale",
      0,NULL,0,0,0,0,0,0},
 
     {"bitop",bitopCommand,-4,
@@ -4477,7 +4477,7 @@ sds genRedisInfoString(const char *section) {
             "active_defrag_misses:%lld\r\n"
             "active_defrag_key_hits:%lld\r\n"
             "active_defrag_key_misses:%lld\r\n"
-            "tracking_used_slots:%llu\r\n",
+            "tracking_total_items:%llu\r\n",
             g_pserver->stat_numconnections,
             g_pserver->stat_numcommands,
             getInstantaneousMetric(STATS_METRIC_COMMAND),
@@ -4505,7 +4505,7 @@ sds genRedisInfoString(const char *section) {
             g_pserver->stat_active_defrag_misses,
             g_pserver->stat_active_defrag_key_hits,
             g_pserver->stat_active_defrag_key_misses,
-            trackingGetUsedSlots());
+            (unsigned long long) trackingGetTotalItems());
     }
 
     /* Replication */

src/server.h

@@ -581,8 +581,8 @@ public:
 #define NOTIFY_EXPIRED (1<<8)     /* x */
 #define NOTIFY_EVICTED (1<<9)     /* e */
 #define NOTIFY_STREAM (1<<10)     /* t */
-#define NOTIFY_KEY_MISS (1<<11)   /* m */
+#define NOTIFY_KEY_MISS (1<<11)   /* m (Note: This one is excluded from NOTIFY_ALL on purpose) */
-#define NOTIFY_ALL (NOTIFY_GENERIC | NOTIFY_STRING | NOTIFY_LIST | NOTIFY_SET | NOTIFY_HASH | NOTIFY_ZSET | NOTIFY_EXPIRED | NOTIFY_EVICTED | NOTIFY_STREAM | NOTIFY_KEY_MISS) /* A flag */
+#define NOTIFY_ALL (NOTIFY_GENERIC | NOTIFY_STRING | NOTIFY_LIST | NOTIFY_SET | NOTIFY_HASH | NOTIFY_ZSET | NOTIFY_EXPIRED | NOTIFY_EVICTED | NOTIFY_STREAM) /* A flag */
 
 /* Get the first bind addr or NULL */
 #define NET_FIRST_BIND_ADDR (g_pserver->bindaddr_count ? g_pserver->bindaddr[0] : NULL)
@@ -2230,7 +2230,7 @@ void trackingRememberKeys(client *c);
 void trackingInvalidateKey(robj *keyobj);
 void trackingInvalidateKeysOnFlush(int dbid);
 void trackingLimitUsedSlots(void);
-unsigned long long trackingGetUsedSlots(void);
+uint64_t trackingGetTotalItems(void);
 
 /* List data type */
 void listTypeTryConversion(robj *subject, robj *value);

src/tracking.cpp

@@ -30,37 +30,22 @@
 
 #include "server.h"
 
-/* The tracking table is constituted by 2^24 radix trees (each tree, and the
+/* The tracking table is constituted by a radix tree of keys, each pointing
- * table itself, are allocated in a lazy way only when needed) tracking
+ * to a radix tree of client IDs, used to track the clients that may have
- * clients that may have certain keys in their local, client side, cache.
+ * certain keys in their local, client side, cache.
- *
- * Keys are grouped into 2^24 slots, in a way similar to Redis Cluster hash
- * slots, however here the function we use is crc64, taking the least
- * significant 24 bits of the output.
  *
  * When a client enables tracking with "CLIENT TRACKING on", each key served to
- * the client is hashed to one of such slots, and Redis will remember what
+ * the client is remembered in the table mapping the keys to the client IDs.
- * client may have keys about such slot. Later, when a key in a given slot is
+ * Later, when a key is modified, all the clients that may have local copy
- * modified, all the clients that may have local copies of keys in that slot
+ * of such key will receive an invalidation message.
- * will receive an invalidation message. There is no distinction of database
- * number: a single table is used.
  *
  * Clients will normally take frequently requested objects in memory, removing
- * them when invalidation messages are received. A strategy clients may use is
+ * them when invalidation messages are received. */
- * to just cache objects in a dictionary, associating to each cached object
+rax *TrackingTable = NULL;
- * some incremental epoch, or just a timestamp. When invalidation messages are
+uint64_t TrackingTableTotalItems = 0; /* Total number of IDs stored across
- * received clients may store, in a different table, the timestamp (or epoch)
+                                         the whole tracking table. This givesn
- * of the invalidation of such given slot: later when accessing objects, the
+                                         an hint about the total memory we
- * eviction of stale objects may be performed in a lazy way by checking if the
+                                         are using server side for CSC. */
- * cached object timestamp is older than the invalidation timestamp for such
- * objects.
- *
- * The output of the 24 bit hash function is very large (more than 16 million
- * possible slots), so clients that may want to use less resources may only
- * use the most significant bits instead of the full 24 bits. */
-#define TRACKING_TABLE_SIZE (1<<24)
-rax **TrackingTable = NULL;
-unsigned long TrackingTableUsedSlots = 0;
 robj *TrackingChannelName;
 
 /* Remove the tracking state from the client 'c'. Note that there is not much
@@ -90,7 +75,7 @@ void enableTracking(client *c, uint64_t redirect_to) {
     c->client_tracking_redirection = redirect_to;
     g_pserver->tracking_clients++;
     if (TrackingTable == NULL) {
-        TrackingTable = (rax**)zcalloc(sizeof(rax*) * TRACKING_TABLE_SIZE, MALLOC_LOCAL);
+        TrackingTable = raxNew();
         TrackingChannelName = createStringObject("__redis__:invalidate",20);
     }
 }
@@ -107,20 +92,21 @@ void trackingRememberKeys(client *c) {
 
     for(int j = 0; j < numkeys; j++) {
         int idx = keys[j];
-        sds sdskey = (sds)ptrFromObj(c->argv[idx]);
+        sds sdskey = szFromObj(c->argv[idx]);
-        uint64_t hash = crc64(0,
+        rax *ids = (rax*)raxFind(TrackingTable,(unsigned char*)sdskey,sdslen(sdskey));
-            (unsigned char*)sdskey,sdslen(sdskey))&(TRACKING_TABLE_SIZE-1);
+        if (ids == raxNotFound) {
-        if (TrackingTable[hash] == NULL) {
+            ids = raxNew();
-            TrackingTable[hash] = raxNew();
+            int inserted = raxTryInsert(TrackingTable,(unsigned char*)sdskey,
-            TrackingTableUsedSlots++;
+                                        sdslen(sdskey),ids, NULL);
+            serverAssert(inserted == 1);
         }
-        raxTryInsert(TrackingTable[hash],
+        if (raxTryInsert(ids,(unsigned char*)&c->id,sizeof(c->id),NULL,NULL))
-            (unsigned char*)&c->id,sizeof(c->id),NULL,NULL);
+            TrackingTableTotalItems++;
     }
     getKeysFreeResult(keys);
 }
 
-void sendTrackingMessage(client *c, long long hash) {
+void sendTrackingMessage(client *c, const char *keyname, size_t keylen) {
     int using_redirection = 0;
     if (c->client_tracking_redirection) {
         client *redir = lookupClientByID(c->client_tracking_redirection);
@@ -146,49 +132,44 @@ void sendTrackingMessage(client *c, long long hash) {
     if (c->resp > 2) {
         addReplyPushLen(c,2);
         addReplyBulkCBuffer(c,"invalidate",10);
-        addReplyLongLong(c,hash);
+        addReplyBulkCBuffer(c,keyname,keylen);
     } else if (using_redirection && c->flags & CLIENT_PUBSUB) {
-        robj *msg = createStringObjectFromLongLong(hash);
+        /* We use a static object to speedup things, however we assume
-        addReplyPubsubMessage(c,TrackingChannelName,msg);
+         * that addReplyPubsubMessage() will not take a reference. */
-        decrRefCount(msg);
+        robj keyobj;
+        initStaticStringObject(keyobj,(char*)keyname);
+        addReplyPubsubMessage(c,TrackingChannelName,&keyobj);
+        serverAssert(keyobj.getrefcount(std::memory_order_relaxed) == 1);
     }
 }
 
-/* Invalidates a caching slot: this is actually the low level implementation
- * of the API that Redis calls externally, that is trackingInvalidateKey(). */
-void trackingInvalidateSlot(uint64_t slot) {
-    if (TrackingTable == NULL || TrackingTable[slot] == NULL) return;
-
-    raxIterator ri;
-    raxStart(&ri,TrackingTable[slot]);
-    raxSeek(&ri,"^",NULL,0);
-    while(raxNext(&ri)) {
-        uint64_t id;
-        memcpy(&id,ri.key,sizeof(id));
-        client *c = lookupClientByID(id);
-        if (c == NULL || !(c->flags & CLIENT_TRACKING)) continue;
-        sendTrackingMessage(c,slot);
-    }
-    raxStop(&ri);
-
-    /* Free the tracking table: we'll create the radix tree and populate it
-     * again if more keys will be modified in this caching slot. */
-    raxFree(TrackingTable[slot]);
-    TrackingTable[slot] = NULL;
-    TrackingTableUsedSlots--;
-}
-
 /* This function is called from signalModifiedKey() or other places in Redis
  * when a key changes value. In the context of keys tracking, our task here is
  * to send a notification to every client that may have keys about such caching
  * slot. */
 void trackingInvalidateKey(robj *keyobj) {
-    if (TrackingTable == NULL || TrackingTableUsedSlots == 0) return;
+    if (TrackingTable == NULL) return;
+    sds sdskey = szFromObj(keyobj);
+    rax *ids = (rax*)raxFind(TrackingTable,(unsigned char*)sdskey,sdslen(sdskey));
+    if (ids == raxNotFound) return;;
 
-    sds sdskey = (sds)ptrFromObj(keyobj);
+    raxIterator ri;
-    uint64_t hash = crc64(0,
+    raxStart(&ri,ids);
-        (unsigned char*)sdskey,sdslen(sdskey))&(TRACKING_TABLE_SIZE-1);
+    raxSeek(&ri,"^",NULL,0);
-    trackingInvalidateSlot(hash);
+    while(raxNext(&ri)) {
+        uint64_t id;
+        memcpy(&id,ri.key,sizeof(id));
+        client *c = lookupClientByID(id);
+        if (c == NULL || !(c->flags & CLIENT_TRACKING)) continue;
+        sendTrackingMessage(c,sdskey,sdslen(sdskey));
+    }
+    raxStop(&ri);
+
+    /* Free the tracking table: we'll create the radix tree and populate it
+     * again if more keys will be modified in this caching slot. */
+    TrackingTableTotalItems -= raxSize(ids);
+    raxFree(ids);
+    raxRemove(TrackingTable,(unsigned char*)sdskey,sdslen(sdskey),NULL);
 }
 
 /* This function is called when one or all the Redis databases are flushed
@@ -205,6 +186,10 @@ void trackingInvalidateKey(robj *keyobj) {
  * we just send the invalidation message to all the clients, but don't
  * flush the table: it will slowly get garbage collected as more keys
  * are modified in the used caching slots. */
+void freeTrackingRadixTree(void *rt) {
+    raxFree((rax*)rt);
+}
+
 void trackingInvalidateKeysOnFlush(int dbid) {
     if (g_pserver->tracking_clients) {
         listNode *ln;
@@ -213,84 +198,69 @@ void trackingInvalidateKeysOnFlush(int dbid) {
         while ((ln = listNext(&li)) != NULL) {
             client *c = (client*)listNodeValue(ln);
             if (c->flags & CLIENT_TRACKING) {
-                sendTrackingMessage(c,-1);
+                sendTrackingMessage(c,"",1);
             }
         }
     }
 
     /* In case of FLUSHALL, reclaim all the memory used by tracking. */
     if (dbid == -1 && TrackingTable) {
-        for (int j = 0; j < TRACKING_TABLE_SIZE && TrackingTableUsedSlots > 0; j++) {
+        raxFreeWithCallback(TrackingTable,freeTrackingRadixTree);
-            if (TrackingTable[j] != NULL) {
+        TrackingTableTotalItems = 0;
-                raxFree(TrackingTable[j]);
-                TrackingTable[j] = NULL;
-                TrackingTableUsedSlots--;
-            }
-        }
-
-        /* If there are no clients with tracking enabled, we can even
-         * reclaim the memory used by the table itself. The code assumes
-         * the table is allocated only if there is at least one client alive
-         * with tracking enabled. */
-        if (g_pserver->tracking_clients == 0) {
-            zfree(TrackingTable);
-            TrackingTable = NULL;
-        }
     }
 }
 
 /* Tracking forces Redis to remember information about which client may have
- * keys about certian caching slots. In workloads where there are a lot of
+ * certain keys. In workloads where there are a lot of reads, but keys are
- * reads, but keys are hardly modified, the amount of information we have
+ * hardly modified, the amount of information we have to remember server side
- * to remember server side could be a lot: for each 16 millions of caching
+ * could be a lot, with the number of keys being totally not bound.
- * slots we may end with a radix tree containing many entries.
  *
- * So Redis allows the user to configure a maximum fill rate for the
+ * So Redis allows the user to configure a maximum number of keys for the
  * invalidation table. This function makes sure that we don't go over the
  * specified fill rate: if we are over, we can just evict informations about
- * random caching slots, and send invalidation messages to clients like if
+ * a random key, and send invalidation messages to clients like if the key was
- * the key was modified. */
+ * modified. */
 void trackingLimitUsedSlots(void) {
     static unsigned int timeout_counter = 0;
-
+    if (TrackingTable == NULL) return;
     if (g_pserver->tracking_table_max_fill == 0) return; /* No limits set. */
-    unsigned int max_slots =
+    size_t max_keys = g_pserver->tracking_table_max_fill;
-        (TRACKING_TABLE_SIZE/100) * g_pserver->tracking_table_max_fill;
+    if (raxSize(TrackingTable) <= max_keys) {
-    if (TrackingTableUsedSlots <= max_slots) {
         timeout_counter = 0;
         return; /* Limit not reached. */
     }
 
-    /* We have to invalidate a few slots to reach the limit again. The effort
+    /* We have to invalidate a few keys to reach the limit again. The effort
      * we do here is proportional to the number of times we entered this
      * function and found that we are still over the limit. */
     int effort = 100 * (timeout_counter+1);
 
-    /* Let's start at a random position, and perform linear probing, in order
+    /* We just remove one key after another by using a random walk. */
-     * to improve cache locality. However once we are able to find an used
+    raxIterator ri;
-     * slot, jump again randomly, in order to avoid creating big holes in the
+    raxStart(&ri,TrackingTable);
-     * table (that will make this funciton use more resourced later). */
     while(effort > 0) {
-        unsigned int idx = rand() % TRACKING_TABLE_SIZE;
-        do {
         effort--;
-            idx = (idx+1) % TRACKING_TABLE_SIZE;
+        raxSeek(&ri,"^",NULL,0);
-            if (TrackingTable[idx] != NULL) {
+        raxRandomWalk(&ri,0);
-                trackingInvalidateSlot(idx);
+        rax *ids = (rax*)ri.data;
-                if (TrackingTableUsedSlots <= max_slots) {
+        TrackingTableTotalItems -= raxSize(ids);
+        raxFree(ids);
+        raxRemove(TrackingTable,ri.key,ri.key_len,NULL);
+        if (raxSize(TrackingTable) <= max_keys) {
             timeout_counter = 0;
+            raxStop(&ri);
             return; /* Return ASAP: we are again under the limit. */
-                } else {
-                    break; /* Jump to next random position. */
         }
     }
-        } while(effort > 0);
+
-    }
+    /* If we reach this point, we were not able to go under the configured
+     * limit using the maximum effort we had for this run. */
+    raxStop(&ri);
     timeout_counter++;
 }
 
 /* This is just used in order to access the amount of used slots in the
  * tracking table. */
-unsigned long long trackingGetUsedSlots(void) {
+uint64_t trackingGetTotalItems(void) {
-    return TrackingTableUsedSlots;
+    return TrackingTableTotalItems;
 }