feat(pprof): Pprof HTTP server service (ChainSafe#1991)

- Add a pprof HTTP server service to dot node
  - `internal/httpserver` package
  - `internal/pprof` package
- Configurable server listening address from flags and toml config file
- Configurable pprof server on/off from flags and toml config file
- Configurable mutex profile fraction from flags and toml config file
- Configurable block profile rate from flags and toml config file
- Pprof documentation
- Remove pprof to file operation and `--cpuprof` and `--memprof` flags

Author: qdm12

chain/dev/config.toml

@@ -38,3 +38,9 @@ port = 8545
 host = "localhost"
 modules = ["system", "author", "chain", "state", "rpc", "grandpa", "offchain", "childstate", "syncstate", "payment"]
 ws-port = 8546
+
+[pprof]
+enabled = false
+listening-address = "localhost:6060"
+block-rate = 0
+mutex-rate = 0

chain/dev/defaults.go

@@ -86,3 +86,21 @@ var (
 	// DefaultWSEnabled enables the WS server
 	DefaultWSEnabled = true
 )
+
+const (
+	// PprofConfig
+
+	// DefaultPprofEnabled to indicate the pprof http server should be enabled or not.
+	DefaultPprofEnabled = true
+
+	// DefaultPprofListeningAddress default pprof HTTP server listening address.
+	DefaultPprofListeningAddress = "localhost:6060"
+
+	// DefaultPprofBlockRate default block profile rate.
+	// Set to 0 to disable profiling.
+	DefaultPprofBlockRate = 0
+
+	// DefaultPprofMutexRate default mutex profile rate.
+	// Set to 0 to disable profiling.
+	DefaultPprofMutexRate = 0
+)

chain/gssmr/config.toml

@@ -39,3 +39,9 @@ port = 8545
 host = "localhost"
 modules = ["system", "author", "chain", "state", "rpc", "grandpa", "offchain", "childstate", "syncstate", "payment"]
 ws-port = 8546
+
+[pprof]
+enabled = false
+listening-address = "localhost:6060"
+block-rate = 0
+mutex-rate = 0

chain/gssmr/defaults.go

@@ -92,3 +92,21 @@ var (
 	// DefaultRPCWSPort rpc websocket port
 	DefaultRPCWSPort = uint32(8546)
 )
+
+const (
+	// PprofConfig
+
+	// DefaultPprofEnabled to indicate the pprof http server should be enabled or not.
+	DefaultPprofEnabled = true
+
+	// DefaultPprofListeningAddress default pprof HTTP server listening address.
+	DefaultPprofListeningAddress = "localhost:6060"
+
+	// DefaultPprofBlockRate default block profile rate.
+	// Set to 0 to disable profiling.
+	DefaultPprofBlockRate = 0
+
+	// DefaultPprofMutexRate default mutex profile rate.
+	// Set to 0 to disable profiling.
+	DefaultPprofMutexRate = 0
+)

chain/kusama/config.toml

@@ -39,3 +39,9 @@ modules = ["system", "author", "chain", "state", "rpc", "grandpa", "offchain", "
 ws-port = 8546
 ws = false
 ws-external = false
+
+[pprof]
+enabled = false
+listening-address = "localhost:6060"
+block-rate = 0
+mutex-rate = 0

chain/kusama/defaults.go

@@ -78,3 +78,21 @@ var (
 	// DefaultRPCWSPort rpc websocket port
 	DefaultRPCWSPort = uint32(8546)
 )
+
+const (
+	// PprofConfig
+
+	// DefaultPprofEnabled to indicate the pprof http server should be enabled or not.
+	DefaultPprofEnabled = false
+
+	// DefaultPprofListeningAddress default pprof HTTP server listening address.
+	DefaultPprofListeningAddress = "localhost:6060"
+
+	// DefaultPprofBlockRate default block profile rate.
+	// Set to 0 to disable profiling.
+	DefaultPprofBlockRate = 0
+
+	// DefaultPprofMutexRate default mutex profile rate.
+	// Set to 0 to disable profiling.
+	DefaultPprofMutexRate = 0
+)

chain/polkadot/config.toml

@@ -35,4 +35,10 @@ enabled = false
 port = 8545
 host = "localhost"
 modules = ["system", "author", "chain", "state", "rpc", "grandpa", "offchain", "childstate", "syncstate", "payment"]
-ws-port = 8546
+ws-port = 8546
+
+[pprof]
+enabled = false
+listening-address = "localhost:6060"
+block-rate = 0
+mutex-rate = 0

chain/polkadot/defaults.go

@@ -79,3 +79,21 @@ var (
 	// DefaultRPCWSPort rpc websocket port
 	DefaultRPCWSPort = uint32(8546)
 )
+
+const (
+	// PprofConfig
+
+	// DefaultPprofEnabled to indicate the pprof http server should be enabled or not.
+	DefaultPprofEnabled = false
+
+	// DefaultPprofListeningAddress default pprof HTTP server listening address.
+	DefaultPprofListeningAddress = "localhost:6060"
+
+	// DefaultPprofBlockRate default block profile rate.
+	// Set to 0 to disable profiling.
+	DefaultPprofBlockRate = 0
+
+	// DefaultPprofMutexRate default mutex profile rate.
+	// Set to 0 to disable profiling.
+	DefaultPprofMutexRate = 0
+)

cmd/gossamer/config.go

@@ -135,6 +135,7 @@ func createDotConfig(ctx *cli.Context) (*dot.Config, error) {
 	setDotCoreConfig(ctx, tomlCfg.Core, &cfg.Core)
 	setDotNetworkConfig(ctx, tomlCfg.Network, &cfg.Network)
 	setDotRPCConfig(ctx, tomlCfg.RPC, &cfg.RPC)
+	setDotPprofConfig(ctx, tomlCfg.Pprof, &cfg.Pprof)
 
 	if rewind := ctx.GlobalInt(RewindFlag.Name); rewind != 0 {
 		cfg.State.Rewind = rewind
@@ -849,3 +850,49 @@ func updateDotConfigFromGenesisData(ctx *cli.Context, cfg *dot.Config) error {
 
 	return nil
 }
+
+func setDotPprofConfig(ctx *cli.Context, tomlCfg ctoml.PprofConfig, cfg *dot.PprofConfig) {
+	if !cfg.Enabled {
+		// only allow to enable pprof from the TOML configuration.
+		// If it is enabled by default, it cannot be disabled.
+		cfg.Enabled = tomlCfg.Enabled
+	}
+
+	if tomlCfg.ListeningAddress != "" {
+		cfg.Settings.ListeningAddress = tomlCfg.ListeningAddress
+	}
+
+	if tomlCfg.BlockRate > 0 {
+		// block rate must be 0 (disabled) by default, since we
+		// cannot disable it here.
+		cfg.Settings.BlockProfileRate = tomlCfg.BlockRate
+	}
+
+	if tomlCfg.MutexRate > 0 {
+		// mutex rate must be 0 (disabled) by default, since we
+		// cannot disable it here.
+		cfg.Settings.MutexProfileRate = tomlCfg.MutexRate
+	}
+
+	// check --pprofserver flag and update node configuration
+	if enabled := ctx.GlobalBool(PprofServerFlag.Name); enabled || cfg.Enabled {
+		cfg.Enabled = true
+	} else if ctx.IsSet(PprofServerFlag.Name) && !enabled {
+		cfg.Enabled = false
+	}
+
+	// check --pprofaddress flag and update node configuration
+	if address := ctx.GlobalString(PprofAddressFlag.Name); address != "" {
+		cfg.Settings.ListeningAddress = address
+	}
+
+	if rate := ctx.GlobalInt(PprofBlockRateFlag.Name); rate > 0 {
+		cfg.Settings.BlockProfileRate = rate
+	}
+
+	if rate := ctx.GlobalInt(PprofMutexRateFlag.Name); rate > 0 {
+		cfg.Settings.MutexProfileRate = rate
+	}
+
+	logger.Debug("pprof configuration: " + cfg.String())
+}

cmd/gossamer/config_test.go

@@ -782,6 +782,7 @@ func TestUpdateConfigFromGenesisJSON(t *testing.T) {
 		Network: testCfg.Network,
 		RPC:     testCfg.RPC,
 		System:  testCfg.System,
+		Pprof:   testCfg.Pprof,
 	}
 
 	cfg, err := createDotConfig(ctx)
@@ -836,6 +837,7 @@ func TestUpdateConfigFromGenesisJSON_Default(t *testing.T) {
 		Network: testCfg.Network,
 		RPC:     testCfg.RPC,
 		System:  testCfg.System,
+		Pprof:   testCfg.Pprof,
 	}
 
 	cfg, err := createDotConfig(ctx)
@@ -894,6 +896,7 @@ func TestUpdateConfigFromGenesisData(t *testing.T) {
 		},
 		RPC:    testCfg.RPC,
 		System: testCfg.System,
+		Pprof:  testCfg.Pprof,
 	}
 
 	cfg, err := createDotConfig(ctx)