Some profiling infrastructure.

I avoided creating any dependency on yourkit. In addition, there was
no way to give arguments to the JVM without losing the ones defined in
ANT_OPTS, which has been a massive pain for a while. So there is now
"jvm.opts" which is simply appended to ANT_OPTS, e.g.

  % ant -Djvm.opts=-verbose
  [echo] Forking with JVM opts: -Xms1536M -Xmx2g -Xss1M -XX:MaxPermSize=192M -XX:+UseParallelGC -verbose

There is a minimal stub defining a profiler interface:

  scala.tools.util.Profiling

Then the yourkit wrapper implements that interface. Once your locker has
been rebuilt once, you can do this:

  ant yourkit.run

And it will build quick.lib/comp with profiling enabled, assuming it
can find the necessary files. See the yourkit.init target for values to
change: or ant -Dyourkit.home=/path/to/it might be enough.

Review by dragos.

1 files changed, 36 insertions, 0 deletions

diff --git a/src/yourkit/scala/tools/util/YourkitProfiling.scala b/src/yourkit/scala/tools/util/YourkitProfiling.scala
new file mode 100644
index 0000000000..d66cdc9ee1
--- /dev/null
+++ b/src/yourkit/scala/tools/util/YourkitProfiling.scala
@@ -0,0 +1,36 @@
+package scala.tools
+package util
+
+import com.yourkit.api._
+import nsc.io._
+
+class YourkitProfiling extends Profiling {
+  @volatile private var active = false
+  private var recordAllocation = false
+  lazy val controller = new Controller
+
+  def startProfiling(): Unit = {
+    if (isActive)
+      return
+
+    active = true
+    daemonize(true) {
+      controller.startCPUProfiling(ProfilingModes.CPU_SAMPLING, Controller.DEFAULT_FILTERS)
+      if (recordAllocation)
+        controller.startAllocationRecording(true, 100, false, 0)
+    }
+  }
+
+  def captureSnapshot() =
+    daemonize(false)(controller.captureSnapshot(ProfilingModes.SNAPSHOT_WITH_HEAP))
+
+  def stopProfiling() = {
+    if (recordAllocation)
+      controller.stopAllocationRecording()
+
+    controller.stopCPUProfiling()
+    active = false
+  }
+
+  def isActive = active
+}
\ No newline at end of file