ContextHolder

7 files changed, 83 insertions, 11 deletions

diff --git a/build.sbt b/build.sbt
index 4790074f..e323a456 100644
--- a/build.sbt
+++ b/build.sbt
@@ -20,10 +20,10 @@ lazy val kamon = (project in file("."))
   .aggregate(core, testkit, coreTests, coreBench)
 
 val commonSettings = Seq(
-  scalaVersion := "2.12.4",
+  scalaVersion := "2.12.7",
   javacOptions += "-XDignore.symbol.file",
   resolvers += Resolver.mavenLocal,
-  crossScalaVersions := Seq("2.12.4", "2.11.8", "2.10.6"),
+  crossScalaVersions := Seq("2.12.7", "2.11.8", "2.10.6"),
   concurrentRestrictions in Global += Tags.limit(Tags.Test, 1),
   scalacOptions ++= Seq(
     "-deprecation",
diff --git a/kamon-core-bench/library/kanela-agent-0.0.400.jar b/kamon-core-bench/library/kanela-agent-0.0.400.jar
new file mode 100644
index 00000000..9ec36fc7
--- /dev/null
+++ b/kamon-core-bench/library/kanela-agent-0.0.400.jar
diff --git a/kamon-core-bench/src/main/scala/kamon/bench/ThreadLocalStorageBenchmark.scala b/kamon-core-bench/src/main/scala/kamon/bench/ThreadLocalStorageBenchmark.scala
index e67a913e..1bd6f4ce 100644
--- a/kamon-core-bench/src/main/scala/kamon/bench/ThreadLocalStorageBenchmark.scala
+++ b/kamon-core-bench/src/main/scala/kamon/bench/ThreadLocalStorageBenchmark.scala
@@ -22,14 +22,23 @@ import kamon.context.Storage.Scope
 import kamon.context.{Context, Key, Storage}
 import org.openjdk.jmh.annotations._
 
-@State(Scope.Benchmark)
+@State(Scope.Thread)
 class ThreadLocalStorageBenchmark {
 
-  val TestKey: Key[Int] = Key.local("test-key", 0)
-  val ContextWithKey: Context = Context.create().withKey(TestKey, 43)
+  var TestKey: Key[Int] = _
+  var ContextWithKey: Context = _
 
-  val TLS: Storage =  new OldThreadLocal
-  val FTLS: Storage =  new Storage.ThreadLocal
+  var TLS: Storage =  _
+  var FTLS: Storage =  _
+
+  @Setup
+  def setup() = {
+    TestKey = Key.local("test-key", 0)
+    ContextWithKey = Context.create().withKey(TestKey, 43)
+
+    TLS =  new OldThreadLocal
+    FTLS =  Storage.ThreadLocal()
+  }
 
 
   @Benchmark
@@ -53,6 +62,17 @@ class ThreadLocalStorageBenchmark {
     scope.close()
     FTLS.current()
   }
+
+  @Benchmark
+  @BenchmarkMode(Array(Mode.AverageTime))
+  @OutputTimeUnit(TimeUnit.NANOSECONDS)
+  @Fork(jvmArgsAppend = Array("-javaagent:library/kanela-agent-0.0.400.jar"))
+  def superFastThreadLocal: Context = {
+    val scope = FTLS.store(ContextWithKey)
+    FTLS.current()
+    scope.close()
+    FTLS.current()
+  }
 }
 
 
diff --git a/kamon-core/src/main/java/kanela/agent/bootstrap/context/ContextHolder.java b/kamon-core/src/main/java/kanela/agent/bootstrap/context/ContextHolder.java
new file mode 100644
index 00000000..ae8d41b6
--- /dev/null
+++ b/kamon-core/src/main/java/kanela/agent/bootstrap/context/ContextHolder.java
@@ -0,0 +1,9 @@
+package kanela.agent.bootstrap.context;
+
+public final class ContextHolder  {
+    public Object value;
+
+    public ContextHolder(Object value) {
+        this.value = value;
+    }
+}
diff --git a/kamon-core/src/main/scala/kamon/context/ContextHolder.scala b/kamon-core/src/main/scala/kamon/context/ContextHolder.scala
new file mode 100644
index 00000000..321d478f
--- /dev/null
+++ b/kamon-core/src/main/scala/kamon/context/ContextHolder.scala
@@ -0,0 +1,3 @@
+//package kanela.agent.bootstrap.context
+//
+//final class ContextHolder(var value: Object)
diff --git a/kamon-core/src/main/scala/kamon/context/Storage.scala b/kamon-core/src/main/scala/kamon/context/Storage.scala
index 2b409592..5ead7db9 100644
--- a/kamon-core/src/main/scala/kamon/context/Storage.scala
+++ b/kamon-core/src/main/scala/kamon/context/Storage.scala
@@ -15,6 +15,10 @@
 
 package kamon.context
 
+import kanela.agent.bootstrap.context.ContextHolder
+
+//import kanela.agent.bootstrap.context.ContextHolder
+
 trait Storage {
   def current(): Context
   def store(context: Context): Storage.Scope
@@ -40,7 +44,15 @@ object Storage {
     * <p> One small change is that we don't use an kamon-defined holder object as that would prevent class unloading.
     *
     * */
-  class ThreadLocal extends Storage {
+
+  object ThreadLocal {
+    def apply(): Storage = {
+      if(classOf[ContextHolder].getClassLoader == null) SuperFastThreadLocal()
+      else FastThreadLocal()
+    }
+  }
+
+  final class FastThreadLocal extends Storage {
     private val tls = new java.lang.ThreadLocal[Array[AnyRef]]() {
       override def initialValue(): Array[AnyRef] =
         Array(Context.Empty)
@@ -61,7 +73,35 @@ object Storage {
     }
   }
 
-  object ThreadLocal {
-    def apply(): ThreadLocal = new ThreadLocal()
+  object FastThreadLocal {
+    def apply(): FastThreadLocal = new FastThreadLocal()
+  }
+
+
+  final class SuperFastThreadLocal extends Storage {
+    private val tls = new java.lang.ThreadLocal[ContextHolder]() {
+      override def initialValue(): ContextHolder = {
+        new ContextHolder(Context.Empty)
+      }
+    }
+
+    override def current(): Context =
+      tls.get().value.asInstanceOf[Context]
+
+    override def store(newContext: Context): Scope = {
+      val ref = tls.get()
+      val previousContext = ref.value
+      ref.value = newContext
+
+      new Scope {
+        override def context: Context = newContext
+        override def close(): Unit = ref.value = previousContext
+      }
+    }
+  }
+
+  object SuperFastThreadLocal {
+    def apply(): SuperFastThreadLocal = new SuperFastThreadLocal()
   }
 }
+
diff --git a/project/build.properties b/project/build.properties
index c091b86c..133a8f19 100644
--- a/project/build.properties
+++ b/project/build.properties
@@ -1 +1 @@
-sbt.version=0.13.16
+sbt.version=0.13.17