Add support for slowlog

libs/common/LightClient.cs

@@ -168,7 +168,7 @@ private async Task<bool> TryConnectSocketAsync(Socket socket, EndPoint endpoint,
                 if (socket.Connected)
                     return true;
             }
-            catch (Exception ex)
+            catch
             {
                 socket.Dispose();
                 return false;

libs/host/Configuration/Options.cs

@@ -313,6 +313,14 @@ internal sealed class Options
         [Option("latency-monitor", Required = false, HelpText = "Track latency of various events.")]
         public bool? LatencyMonitor { get; set; }
 
+        [IntRangeValidation(0, int.MaxValue)]
+        [Option("slowlog-log-slower-than", Required = false, HelpText = "Threshold (microseconds) for logging command in the slow log. 0 to disable.")]
+        public int SlowLogThreshold { get; set; }
+
+        [IntRangeValidation(0, int.MaxValue)]
+        [Option("slowlog-max-len", Required = false, HelpText = "Maximum number of slow log entries to keep.")]
+        public int SlowLogMaxEntries { get; set; }
+
         [IntRangeValidation(0, int.MaxValue)]
         [Option("metrics-sampling-freq", Required = false, HelpText = "Metrics sampling frequency in seconds. Value of 0 disables metrics monitor task.")]
         public int MetricsSamplingFrequency { get; set; }
@@ -654,6 +662,11 @@ public GarnetServerOptions GetServerOptions(ILogger logger = null)
                 CompactionForceDelete = true;
             }
 
+            if (SlowLogThreshold > 0)
+            {
+                if (SlowLogThreshold < 100)
+                    throw new Exception("SlowLogThreshold must be at least 100 microseconds.");
+            }
             return new GarnetServerOptions(logger)
             {
                 EndPoint = endpoint,
@@ -723,6 +736,8 @@ public GarnetServerOptions GetServerOptions(ILogger logger = null)
                     ServerCertificateRequired.GetValueOrDefault(),
                     logger: logger) : null,
                 LatencyMonitor = LatencyMonitor.GetValueOrDefault(),
+                SlowLogThreshold = SlowLogThreshold,
+                SlowLogMaxEntries = SlowLogMaxEntries,
                 MetricsSamplingFrequency = MetricsSamplingFrequency,
                 LogLevel = LogLevel,
                 LoggingFrequency = LoggingFrequency,

libs/host/Configuration/Redis/RedisOptions.cs

@@ -88,6 +88,12 @@ internal class RedisOptions
 
         [RedisOption("unixsocketperm", nameof(Options.UnixSocketPermission))]
         public Option<int> UnixSocketPermission { get; set; }
+
+        [RedisOption("slowlog-log-slower-than", nameof(Options.SlowLogThreshold))]
+        public Option<int> SlowLogLogSlowerThan { get; set; }
+
+        [RedisOption("slowlog-max-len", nameof(Options.SlowLogMaxEntries))]
+        public Option<int> SlowLogMaxLen { get; set; }
     }
 
     /// <summary>

libs/host/defaults.conf

@@ -230,6 +230,12 @@
 	/* Track latency of various events. */
 	"LatencyMonitor" : false,
 
+	/* Threshold (microseconds) for logging command in the slow log. 0 to disable. */
+	"SlowLogThreshold": 0,
+
+	/* Maximum number of slow log entries to keep. */
+	"SlowLogMaxEntries": 128,
+
 	/* Metrics sampling frequency in seconds. Value of 0 disables metrics monitor task. */
 	"MetricsSamplingFrequency" : 0,
 

libs/resources/RespCommandsDocs.json

@@ -6414,6 +6414,52 @@
       }
     ]
   },
+  {
+    "Command": "SLOWLOG",
+    "Name": "SLOWLOG",
+    "Summary": "A container for slow log commands.",
+    "Group": "Server",
+    "Complexity": "Depends on subcommand.",
+    "SubCommands": [
+      {
+        "Command": "SLOWLOG_GET",
+        "Name": "SLOWLOG|GET",
+        "Summary": "Returns the slow log\u0027s entries.",
+        "Group": "Server",
+        "Complexity": "O(N) where N is the number of entries returned",
+        "Arguments": [
+          {
+            "TypeDiscriminator": "RespCommandBasicArgument",
+            "Name": "COUNT",
+            "DisplayText": "count",
+            "Type": "Integer",
+            "ArgumentFlags": "Optional"
+          }
+        ]
+      },
+      {
+        "Command": "SLOWLOG_HELP",
+        "Name": "SLOWLOG|HELP",
+        "Summary": "Show helpful text about the different subcommands",
+        "Group": "Server",
+        "Complexity": "O(1)"
+      },
+      {
+        "Command": "SLOWLOG_LEN",
+        "Name": "SLOWLOG|LEN",
+        "Summary": "Returns the number of entries in the slow log.",
+        "Group": "Server",
+        "Complexity": "O(1)"
+      },
+      {
+        "Command": "SLOWLOG_RESET",
+        "Name": "SLOWLOG|RESET",
+        "Summary": "Clears all entries from the slow log.",
+        "Group": "Server",
+        "Complexity": "O(N) where N is the number of entries in the slowlog"
+      }
+    ]
+  },
   {
     "Command": "SMEMBERS",
     "Name": "SMEMBERS",

libs/resources/RespCommandsInfo.json

@@ -1761,7 +1761,7 @@
     "FirstKey": 1,
     "LastKey": 1,
     "Step": 1,
-    "AclCategories": "Hash, Write, Admin, Garnet",
+    "AclCategories": "Admin, Hash, Write, Garnet",
     "KeySpecifications": [
       {
         "BeginSearch": {
@@ -4152,6 +4152,55 @@
     "Flags": "Admin, NoAsyncLoading, NoScript, Stale",
     "AclCategories": "Admin, Dangerous, Slow"
   },
+  {
+    "Command": "SLOWLOG",
+    "Name": "SLOWLOG",
+    "Arity": -2,
+    "AclCategories": "Slow",
+    "SubCommands": [
+      {
+        "Command": "SLOWLOG_GET",
+        "Name": "SLOWLOG|GET",
+        "Arity": -2,
+        "Flags": "Admin, Loading, Stale",
+        "AclCategories": "Admin, Dangerous, Slow",
+        "Tips": [
+          "request_policy:all_nodes",
+          "nondeterministic_output"
+        ]
+      },
+      {
+        "Command": "SLOWLOG_HELP",
+        "Name": "SLOWLOG|HELP",
+        "Arity": 2,
+        "Flags": "Loading, Stale",
+        "AclCategories": "Slow"
+      },
+      {
+        "Command": "SLOWLOG_LEN",
+        "Name": "SLOWLOG|LEN",
+        "Arity": 2,
+        "Flags": "Admin, Loading, Stale",
+        "AclCategories": "Admin, Dangerous, Slow",
+        "Tips": [
+          "request_policy:all_nodes",
+          "response_policy:agg_sum",
+          "nondeterministic_output"
+        ]
+      },
+      {
+        "Command": "SLOWLOG_RESET",
+        "Name": "SLOWLOG|RESET",
+        "Arity": 2,
+        "Flags": "Admin, Loading, Stale",
+        "AclCategories": "Admin, Dangerous, Slow",
+        "Tips": [
+          "request_policy:all_nodes",
+          "response_policy:all_succeeded"
+        ]
+      }
+    ]
+  },
   {
     "Command": "SMEMBERS",
     "Name": "SMEMBERS",

libs/server/Metrics/Latency/GarnetLatencyMetricsSession.cs

@@ -57,6 +57,13 @@ public void Start(LatencyMetricsType cmd)
             metrics[idx].Start();
         }
 
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public long Get(LatencyMetricsType cmd)
+        {
+            int idx = (int)cmd;
+            return metrics[idx].startTimestamp;
+        }
+
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public void StopAndSwitch(LatencyMetricsType oldCmd, LatencyMetricsType newCmd)
         {

libs/server/Metrics/Latency/RespLatencyHelp.cs

@@ -18,12 +18,12 @@ public static List<string> GetLatencyCommands()
         {
             return new List<string>()
             {
-                "LATENCY<subcommand>[< arg > [value][opt]...]. Subcommands are:",
+                "LATENCY <subcommand> [<arg> [value] [opt] ...]. Subcommands are:",
                 "HISTOGRAM [EVENT [EVENT...]]",
-                "\t Return latency histogram of or more <event> classes.",
+                "\tReturn latency histogram of one or more <event> classes.",
                 "\tIf no commands are specified then all histograms are replied",
-                "RESET [EVENT [EVENT...]]" +
-                "\tReset latency data of one or more <event> classes." +
+                "RESET [EVENT [EVENT...]]",
+                "\tReset latency data of one or more <event> classes.",
                 "\t(default: reset all data for all event classes).",
                 "HELP",
                 "\tPrints this help"