Add pprof module for profiling (#133)

CHANGES.md

@@ -7,6 +7,7 @@ Release Notes.
 #### Features
 * Upgrade LLVM to `18`.
 * Support propagation the excluding namespaces in the access log to the backend.
+* Add `pprof` module for observe self.
 
 #### Bug Fixes
 * Fixed the issue where `conntrack` could not find the Reply IP in the access log module.

configs/rover_configs.yaml

@@ -146,4 +146,10 @@ access_log:
     # The count of parallel protocol analyzer
     parallels: ${ROVER_ACCESS_LOG_PROTOCOL_ANALYZE_PARALLELS:2}
     # The size of per paralleled analyzer queue
-    queue_size: ${ROVER_ACCESS_LOG_PROTOCOL_ANALYZE_QUEUE_SIZE:5000}
+    queue_size: ${ROVER_ACCESS_LOG_PROTOCOL_ANALYZE_QUEUE_SIZE:5000}
+
+pprof:
+  # Is active the pprof
+  active: ${ROVER_PPROF_ACTIVE:false}
+  # The bind port of the pprof HTTP server
+  port: ${ROVER_PPROF_PORT:6060}

docs/en/setup/configuration/pprof.md

@@ -0,0 +1,18 @@
+# Pprof 
+
+Pprof is a feature to collect self runtime profiling data through `pprof` module.
+
+## Configuration
+
+| Name      | Default | Environment Key      | Description                         |
+|-----------|---------|----------------------|-------------------------------------|
+| `enabled` | `false` | `ROVER_PPROF_ACTIVE` | Enable pprof module.                |
+| `port`    | `6060`  | `ROVER_PPROF_PORT`   | The HTTP port to expose pprof data. |
+
+## Expose Paths
+
+- `/debug/pprof/`: The root path to access pprof data.
+- `/debug/pprof/cmdline`: The command line invocation of the current program.
+- `/debug/pprof/profile`: A pprof-formatted snapshot of the current program.
+- `/debug/pprof/symbol`: The symbol table of the current program.
+- `/debug/pprof/trace`: A trace of the current program.

docs/en/setup/overview.md

@@ -27,6 +27,7 @@ The SkyWalking Rover requires specialized protocols to communicate with SkyWalki
 2. [Service Discovery](configuration/service-discovery.md) includes advanced setups about the ways of discovering services on your Kubernetes cluster. 
 3. [Access logs](./configuration/traffic.md) reports L2 to L4 network traffic relative information through access logs, to help OAP backend to do topology and metrics analysis.
 4. [Profiling](./configuration/profiling.md) is an on-demand feature to enhance general observability besides access logs. It provides eBPF powered process ON_CPU, OFF_CPU profiling and network advanced profiling to link HTTP traffic with SkyWalking and Zipkin traces. 
+5. [Pprof](./configuration/pprof.md) is a feature to collect self runtime profiling data.
 
 To adjust the configurations, refer to [Overriding Setting](./configuration/override-settings.md) document for more details.
 

pkg/boot/register.go

@@ -22,6 +22,7 @@ import (
 	"github.com/apache/skywalking-rover/pkg/core"
 	"github.com/apache/skywalking-rover/pkg/logger"
 	"github.com/apache/skywalking-rover/pkg/module"
+	"github.com/apache/skywalking-rover/pkg/pprof"
 	"github.com/apache/skywalking-rover/pkg/process"
 	"github.com/apache/skywalking-rover/pkg/profiling"
 )
@@ -33,4 +34,5 @@ func init() {
 	module.Register(process.NewModule())
 	module.Register(profiling.NewModule())
 	module.Register(accesslog.NewModule())
+	module.Register(pprof.NewModule())
 }

pkg/pprof/config.go

@@ -0,0 +1,30 @@
+// Licensed to Apache Software Foundation (ASF) under one or more contributor
+// license agreements. See the NOTICE file distributed with
+// this work for additional information regarding copyright
+// ownership. Apache Software Foundation (ASF) licenses this file to you under
+// the Apache License, Version 2.0 (the "License"); you may
+// not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+package pprof
+
+import "github.com/apache/skywalking-rover/pkg/module"
+
+type Config struct {
+	module.Config `mapstructure:",squash"`
+
+	Port int `mapstructure:"port"`
+}
+
+func (c *Config) IsActive() bool {
+	return c.Active
+}

pkg/pprof/module.go

@@ -0,0 +1,93 @@
+// Licensed to Apache Software Foundation (ASF) under one or more contributor
+// license agreements. See the NOTICE file distributed with
+// this work for additional information regarding copyright
+// ownership. Apache Software Foundation (ASF) licenses this file to you under
+// the Apache License, Version 2.0 (the "License"); you may
+// not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+package pprof
+
+import (
+	"context"
+	"fmt"
+	"net/http"
+	"net/http/pprof"
+	"sync"
+	"time"
+
+	"github.com/apache/skywalking-rover/pkg/module"
+)
+
+const ModuleName = "pprof"
+
+type Module struct {
+	config *Config
+
+	mutex  sync.Mutex
+	server *http.Server
+
+	shutdown bool
+}
+
+func NewModule() *Module {
+	return &Module{config: &Config{}}
+}
+
+func (m *Module) Name() string {
+	return ModuleName
+}
+
+func (m *Module) RequiredModules() []string {
+	return nil
+}
+
+func (m *Module) Config() module.ConfigInterface {
+	return m.config
+}
+
+func (m *Module) Start(ctx context.Context, mgr *module.Manager) error {
+	mux := http.NewServeMux()
+	mux.HandleFunc("/debug/pprof/", pprof.Index)
+	mux.HandleFunc("/debug/pprof/cmdline", pprof.Cmdline)
+	mux.HandleFunc("/debug/pprof/profile", pprof.Profile)
+	mux.HandleFunc("/debug/pprof/symbol", pprof.Symbol)
+	mux.HandleFunc("/debug/pprof/trace", pprof.Trace)
+
+	m.mutex.Lock()
+	defer m.mutex.Unlock()
+
+	m.server = &http.Server{
+		Addr:              fmt.Sprintf(":%d", m.config.Port),
+		ReadHeaderTimeout: 3 * time.Second,
+		Handler:           mux,
+	}
+	go func() {
+		m.shutdown = false
+		err := m.server.ListenAndServe()
+		if err != nil && !m.shutdown {
+			mgr.ShutdownModules(err)
+		}
+	}()
+	return nil
+}
+
+func (m *Module) NotifyStartSuccess() {
+}
+
+func (m *Module) Shutdown(ctx context.Context, mgr *module.Manager) error {
+	m.shutdown = true
+	if m.server != nil {
+		return m.server.Shutdown(ctx)
+	}
+	return nil
+}