Instantaneous ops/sec figure in INFO output.

src/redis.c

@@ -616,6 +616,31 @@ void updateLRUClock(void) {
                                                 REDIS_LRU_CLOCK_MAX;
 }
 
+
+/* Add a sample to the operations per second array of samples. */
+void trackOperationsPerSecond(void) {
+    long long t = mstime() - server.ops_sec_last_sample_time;
+    long long ops = server.stat_numcommands - server.ops_sec_last_sample_ops;
+    long long ops_sec;
+
+    ops_sec = t > 0 ? (ops*1000/t) : 0;
+
+    server.ops_sec_samples[server.ops_sec_idx] = ops_sec;
+    server.ops_sec_idx = (server.ops_sec_idx+1) % REDIS_OPS_SEC_SAMPLES;
+    server.ops_sec_last_sample_time = mstime();
+    server.ops_sec_last_sample_ops = server.stat_numcommands;
+}
+
+/* Return the mean of all the samples. */
+long long getOperationsPerSecond(void) {
+    int j;
+    long long sum = 0;
+
+    for (j = 0; j < REDIS_OPS_SEC_SAMPLES; j++)
+        sum += server.ops_sec_samples[j];
+    return sum / REDIS_OPS_SEC_SAMPLES;
+}
+
 int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientData) {
     int j, loops = server.cronloops;
     REDIS_NOTUSED(eventLoop);
@@ -628,6 +653,8 @@ int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientData) {
      * To access a global var is faster than calling time(NULL) */
     server.unixtime = time(NULL);
 
+    trackOperationsPerSecond();
+
     /* We have just 22 bits per object for LRU information.
      * So we use an (eventually wrapping) LRU clock with 10 seconds resolution.
      * 2^22 bits with 10 seconds resoluton is more or less 1.5 years.
@@ -1091,6 +1118,10 @@ void initServer() {
     server.stat_peak_memory = 0;
     server.stat_fork_time = 0;
     server.stat_rejected_conn = 0;
+    memset(server.ops_sec_samples,0,sizeof(server.ops_sec_samples));
+    server.ops_sec_idx = 0;
+    server.ops_sec_last_sample_time = mstime();
+    server.ops_sec_last_sample_ops = 0;
     server.unixtime = time(NULL);
     server.lastbgsave_status = REDIS_OK;
     server.stop_writes_on_bgsave_err = 1;
@@ -1726,6 +1757,7 @@ sds genRedisInfoString(char *section) {
             "# Stats\r\n"
             "total_connections_received:%lld\r\n"
             "total_commands_processed:%lld\r\n"
+            "instantaneous_ops_per_sec:%lld\r\n"
             "rejected_connections:%lld\r\n"
             "expired_keys:%lld\r\n"
             "evicted_keys:%lld\r\n"
@@ -1736,6 +1768,7 @@ sds genRedisInfoString(char *section) {
             "latest_fork_usec:%lld\r\n",
             server.stat_numconnections,
             server.stat_numcommands,
+            getOperationsPerSecond(),
             server.stat_rejected_conn,
             server.stat_expiredkeys,
             server.stat_evictedkeys,

src/redis.h

@@ -59,6 +59,7 @@
 #define REDIS_REPL_PING_SLAVE_PERIOD 10
 
 #define REDIS_RUN_ID_SIZE 40
+#define REDIS_OPS_SEC_SAMPLES 16
 
 /* Protocol and I/O related defines */
 #define REDIS_MAX_QUERYBUF_LEN  (1024*1024*1024) /* 1GB max query buffer. */
@@ -606,6 +607,12 @@ struct redisServer {
     long long slowlog_entry_id;     /* SLOWLOG current entry ID */
     long long slowlog_log_slower_than; /* SLOWLOG time limit (to get logged) */
     unsigned long slowlog_max_len;     /* SLOWLOG max number of items logged */
+    /* The following two are used to track instantaneous "load" in terms
+     * of operations per second. */
+    long long ops_sec_last_sample_time; /* Timestamp of last sample (in ms) */
+    long long ops_sec_last_sample_ops;  /* numcommands in last sample */
+    long long ops_sec_samples[REDIS_OPS_SEC_SAMPLES];
+    int ops_sec_idx;
     /* Configuration */
     int verbosity;                  /* Loglevel in redis.conf */
     int maxidletime;                /* Client timeout in seconds */