Merge pull request #2151 from fjl/debug-api

internal/debug: APIs for profiling and tracing

1 files changed, 64 insertions, 0 deletions

diff --git a/internal/debug/trace.go b/internal/debug/trace.go
new file mode 100644
index 000000000..45637977a
--- /dev/null
+++ b/internal/debug/trace.go
@@ -0,0 +1,64 @@
+// Copyright 2016 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+//+build go1.5
+
+package debug
+
+import (
+	"errors"
+	"os"
+	"runtime/trace"
+
+	"github.com/ethereum/go-ethereum/logger"
+	"github.com/ethereum/go-ethereum/logger/glog"
+)
+
+// StartTrace turns on tracing, writing to the given file.
+func (h *HandlerT) StartTrace(file string) error {
+	h.mu.Lock()
+	defer h.mu.Unlock()
+	if h.traceW != nil {
+		return errors.New("trace already in progress")
+	}
+	f, err := os.Create(expandHome(file))
+	if err != nil {
+		return err
+	}
+	if err := trace.Start(f); err != nil {
+		f.Close()
+		return err
+	}
+	h.traceW = f
+	h.traceFile = file
+	glog.V(logger.Info).Infoln("trace started, writing to", h.traceFile)
+	return nil
+}
+
+// StopTrace stops an ongoing trace.
+func (h *HandlerT) StopTrace() error {
+	h.mu.Lock()
+	defer h.mu.Unlock()
+	trace.Stop()
+	if h.traceW == nil {
+		return errors.New("trace not in progress")
+	}
+	glog.V(logger.Info).Infoln("done writing trace to", h.traceFile)
+	h.traceW.Close()
+	h.traceW = nil
+	h.traceFile = ""
+	return nil
+}