HADOOP-17424. Replace HTrace with No-Op tracer

hadoop-client-modules/hadoop-client-api/pom.xml

@@ -126,9 +126,7 @@
                       <excludes>
                         <exclude>org/apache/hadoop/*</exclude>
                         <exclude>org/apache/hadoop/**/*</exclude>
-                        <!-- Our non-shaded htrace and logging libraries -->
-                        <exclude>org/apache/htrace/*</exclude>
-                        <exclude>org/apache/htrace/**/*</exclude>
+                        <!-- Our non-shaded logging libraries -->
                         <exclude>org/slf4j/*</exclude>
                         <exclude>org/slf4j/**/*</exclude>
                         <exclude>org/apache/commons/logging/*</exclude>

hadoop-client-modules/hadoop-client-check-invariants/pom.xml

@@ -80,8 +80,6 @@
                          but enforcer still sees it.
                     -->
                     <exclude>org.apache.hadoop:hadoop-annotations</exclude>
-                    <!-- We leave HTrace as an unshaded dependnecy on purpose so that tracing within a JVM will work -->
-                    <exclude>org.apache.htrace:htrace-core4</exclude>
                     <!-- Leave slf4j unshaded so downstream users can configure logging. -->
                     <exclude>org.slf4j:slf4j-api</exclude>
                     <!-- Leave commons-logging unshaded so downstream users can configure logging. -->

hadoop-client-modules/hadoop-client-check-test-invariants/pom.xml

@@ -84,8 +84,6 @@
                          but enforcer still sees it.
                     -->
                     <exclude>org.apache.hadoop:hadoop-annotations</exclude>
-                    <!-- We leave HTrace as an unshaded dependnecy on purpose so that tracing within a JVM will work -->
-                    <exclude>org.apache.htrace:htrace-core4</exclude>
                     <!-- Leave slf4j unshaded so downstream users can configure logging. -->
                     <exclude>org.slf4j:slf4j-api</exclude>
                     <!-- Leave commons-logging unshaded so downstream users can configure logging. -->

hadoop-client-modules/hadoop-client-minicluster/pom.xml

@@ -672,7 +672,6 @@
                       <exclude>org.apache.hadoop:hadoop-client-api</exclude>
                       <exclude>org.apache.hadoop:hadoop-client-runtime</exclude>
                       <!-- Fine to expose our purposefully not-shaded deps as dependencies -->
-                      <exclude>org.apache.htrace:htrace-core4</exclude>
                       <exclude>org.slf4j:slf4j-api</exclude>
                       <exclude>commons-logging:commons-logging</exclude>
                       <exclude>junit:junit</exclude>
@@ -870,9 +869,7 @@
                       <excludes>
                         <exclude>org/apache/hadoop/*</exclude>
                         <exclude>org/apache/hadoop/**/*</exclude>
-                        <!-- Our non-shaded htrace and logging libraries -->
-                        <exclude>org/apache/htrace/*</exclude>
-                        <exclude>org/apache/htrace/**/*</exclude>
+                        <!-- Our non-shaded logging libraries -->
                         <exclude>org/slf4j/*</exclude>
                         <exclude>org/slf4j/**/*</exclude>
                         <exclude>org/apache/commons/logging/*</exclude>

hadoop-client-modules/hadoop-client-runtime/pom.xml

@@ -75,15 +75,9 @@
     </dependency>
     <!-- Since hadoop-client is listed as optional, we have to list transitive
          dependencies that we still want to show up.
-         * HTrace
          * Slf4j API
          * commons-logging
       -->
-    <dependency>
-      <groupId>org.apache.htrace</groupId>
-      <artifactId>htrace-core4</artifactId>
-      <scope>runtime</scope>
-    </dependency>
     <dependency>
       <groupId>org.slf4j</groupId>
       <artifactId>slf4j-api</artifactId>
@@ -146,8 +140,6 @@
                     <excludes>
                       <!-- We need a filter that matches just those things that aer included in the api jar -->
                       <exclude>org.apache.hadoop:hadoop-client-api</exclude>
-                      <!-- Leave HTrace as an unshaded dependency on purpose, since a static class member is used to trace within a given JVM instance -->
-                      <exclude>org.apache.htrace:htrace-core4</exclude>
                       <!-- Leave slf4j unshaded so downstream users can configure logging. -->
                       <exclude>org.slf4j:slf4j-api</exclude>
                       <!-- Leave commons-logging unshaded so downstream users can configure logging. -->
@@ -250,9 +242,7 @@
                       <excludes>
                         <exclude>org/apache/hadoop/*</exclude>
                         <exclude>org/apache/hadoop/**/*</exclude>
-                        <!-- Our non-shaded htrace and logging libraries -->
-                        <exclude>org/apache/htrace/*</exclude>
-                        <exclude>org/apache/htrace/**/*</exclude>
+                        <!-- Our non-shaded logging libraries -->
                         <exclude>org/slf4j/*</exclude>
                         <exclude>org/slf4j/**/*</exclude>
                         <exclude>org/apache/commons/logging/*</exclude>

hadoop-common-project/hadoop-common/pom.xml

@@ -286,10 +286,6 @@
       <scope>test</scope>
     </dependency>
 
-    <dependency>
-      <groupId>org.apache.htrace</groupId>
-      <artifactId>htrace-core4</artifactId>
-    </dependency>
     <dependency>
       <groupId>org.apache.zookeeper</groupId>
       <artifactId>zookeeper</artifactId>

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/FSOutputSummer.java

@@ -21,7 +21,7 @@
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.classification.InterfaceStability;
 import org.apache.hadoop.util.DataChecksum;
-import org.apache.htrace.core.TraceScope;
+import org.apache.hadoop.tracing.TraceScope;
 
 import java.io.IOException;
 import java.io.OutputStream;

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/FileContext.java

@@ -67,7 +67,7 @@
 
 import org.apache.hadoop.thirdparty.com.google.common.base.Preconditions;
 import org.apache.hadoop.thirdparty.com.google.common.annotations.VisibleForTesting;
-import org.apache.htrace.core.Tracer;
+import org.apache.hadoop.tracing.Tracer;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/FileSystem.java

@@ -83,8 +83,8 @@
 import org.apache.hadoop.util.ReflectionUtils;
 import org.apache.hadoop.util.ShutdownHookManager;
 import org.apache.hadoop.util.StringUtils;
-import org.apache.htrace.core.Tracer;
-import org.apache.htrace.core.TraceScope;
+import org.apache.hadoop.tracing.Tracer;
+import org.apache.hadoop.tracing.TraceScope;
 
 import org.apache.hadoop.thirdparty.com.google.common.base.Preconditions;
 import org.apache.hadoop.thirdparty.com.google.common.annotations.VisibleForTesting;

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/FsShell.java

@@ -35,8 +35,8 @@
 import org.apache.hadoop.util.StringUtils;
 import org.apache.hadoop.util.Tool;
 import org.apache.hadoop.util.ToolRunner;
-import org.apache.htrace.core.TraceScope;
-import org.apache.htrace.core.Tracer;
+import org.apache.hadoop.tracing.TraceScope;
+import org.apache.hadoop.tracing.Tracer;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/FsTracer.java

@@ -22,7 +22,7 @@
 import org.apache.hadoop.classification.InterfaceStability;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.tracing.TraceUtils;
-import org.apache.htrace.core.Tracer;
+import org.apache.hadoop.tracing.Tracer;
 
 /**
  * Holds the HTrace Tracer used for FileSystem operations.
@@ -47,18 +47,6 @@ public static synchronized Tracer get(Configuration conf) {
     return instance;
   }
 
-  @VisibleForTesting
-  public static synchronized void clear() {
-    if (instance == null) {
-      return;
-    }
-    try {
-      instance.close();
-    } finally {
-      instance = null;
-    }
-  }
-
   private FsTracer() {
   }
 }

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/Globber.java

@@ -27,8 +27,8 @@
 import org.apache.hadoop.classification.InterfaceStability;
 import org.apache.hadoop.util.DurationInfo;
 
-import org.apache.htrace.core.TraceScope;
-import org.apache.htrace.core.Tracer;
+import org.apache.hadoop.tracing.TraceScope;
+import org.apache.hadoop.tracing.Tracer;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/ipc/Client.java

@@ -54,8 +54,8 @@
 import org.apache.hadoop.util.StringUtils;
 import org.apache.hadoop.util.Time;
 import org.apache.hadoop.util.concurrent.AsyncGet;
-import org.apache.htrace.core.Span;
-import org.apache.htrace.core.Tracer;
+import org.apache.hadoop.tracing.Span;
+import org.apache.hadoop.tracing.Tracer;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/ipc/ProtobufRpcEngine.java

@@ -39,8 +39,8 @@
 import org.apache.hadoop.security.token.TokenIdentifier;
 import org.apache.hadoop.util.Time;
 import org.apache.hadoop.util.concurrent.AsyncGet;
-import org.apache.htrace.core.TraceScope;
-import org.apache.htrace.core.Tracer;
+import org.apache.hadoop.tracing.TraceScope;
+import org.apache.hadoop.tracing.Tracer;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/ipc/ProtobufRpcEngine2.java

@@ -35,8 +35,8 @@
 import org.apache.hadoop.security.token.TokenIdentifier;
 import org.apache.hadoop.util.Time;
 import org.apache.hadoop.util.concurrent.AsyncGet;
-import org.apache.htrace.core.TraceScope;
-import org.apache.htrace.core.Tracer;
+import org.apache.hadoop.tracing.Tracer;
+import org.apache.hadoop.tracing.TraceScope;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/ipc/Server.java

@@ -99,6 +99,7 @@
 import org.apache.hadoop.ipc.protobuf.RpcHeaderProtos.RpcSaslProto;
 import org.apache.hadoop.ipc.protobuf.RpcHeaderProtos.RpcSaslProto.SaslAuth;
 import org.apache.hadoop.ipc.protobuf.RpcHeaderProtos.RpcSaslProto.SaslState;
+import org.apache.hadoop.ipc.protobuf.RpcHeaderProtos.RPCTraceInfoProto;
 import org.apache.hadoop.net.NetUtils;
 import org.apache.hadoop.security.AccessControlException;
 import org.apache.hadoop.security.SaslPropertiesResolver;
@@ -118,10 +119,11 @@
 import org.apache.hadoop.util.ProtoUtil;
 import org.apache.hadoop.util.StringUtils;
 import org.apache.hadoop.util.Time;
-import org.apache.htrace.core.SpanId;
-import org.apache.htrace.core.TraceScope;
-import org.apache.htrace.core.Tracer;
-
+import org.apache.hadoop.tracing.Span;
+import org.apache.hadoop.tracing.SpanContext;
+import org.apache.hadoop.tracing.TraceScope;
+import org.apache.hadoop.tracing.Tracer;
+import org.apache.hadoop.tracing.TraceUtils;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import org.apache.hadoop.thirdparty.com.google.common.annotations.VisibleForTesting;
 import org.apache.hadoop.thirdparty.protobuf.ByteString;
@@ -783,7 +785,7 @@ public static class Call implements Schedulable,
     private AtomicInteger responseWaitCount = new AtomicInteger(1);
     final RPC.RpcKind rpcKind;
     final byte[] clientId;
-    private final TraceScope traceScope; // the HTrace scope on the server side
+    private final Span span; // the trace span on the server side
     private final CallerContext callerContext; // the call context
     private boolean deferredResponse = false;
     private int priorityLevel;
@@ -798,7 +800,7 @@ public static class Call implements Schedulable,
 
     Call(Call call) {
       this(call.callId, call.retryCount, call.rpcKind, call.clientId,
-          call.traceScope, call.callerContext);
+          call.span, call.callerContext);
     }
 
     Call(int id, int retryCount, RPC.RpcKind kind, byte[] clientId) {
@@ -812,14 +814,14 @@ public Call(int id, int retryCount, Void ignore1, Void ignore2,
     }
 
     Call(int id, int retryCount, RPC.RpcKind kind, byte[] clientId,
-        TraceScope traceScope, CallerContext callerContext) {
+        Span span, CallerContext callerContext) {
       this.callId = id;
       this.retryCount = retryCount;
       this.timestampNanos = Time.monotonicNowNanos();
       this.responseTimestampNanos = timestampNanos;
       this.rpcKind = kind;
       this.clientId = clientId;
-      this.traceScope = traceScope;
+      this.span = span;
       this.callerContext = callerContext;
       this.clientStateId = Long.MIN_VALUE;
       this.isCallCoordinated = false;
@@ -988,8 +990,8 @@ private class RpcCall extends Call {
 
     RpcCall(Connection connection, int id, int retryCount,
         Writable param, RPC.RpcKind kind, byte[] clientId,
-        TraceScope traceScope, CallerContext context) {
-      super(id, retryCount, kind, clientId, traceScope, context);
+        Span span, CallerContext context) {
+      super(id, retryCount, kind, clientId, span, context);
       this.connection = connection;
       this.rpcRequest = param;
     }
@@ -2672,19 +2674,24 @@ private void processRpcRequest(RpcRequestHeaderProto header,
         throw new FatalRpcServerException(
             RpcErrorCodeProto.FATAL_DESERIALIZING_REQUEST, err);
       }
-        
-      TraceScope traceScope = null;
+
+      Span span = null;
       if (header.hasTraceInfo()) {
-        if (tracer != null) {
-          // If the incoming RPC included tracing info, always continue the
-          // trace
-          SpanId parentSpanId = new SpanId(
-              header.getTraceInfo().getTraceId(),
-              header.getTraceInfo().getParentId());
-          traceScope = tracer.newScope(
-              RpcClientUtil.toTraceName(rpcRequest.toString()),
-              parentSpanId);
-          traceScope.detach();
+        RPCTraceInfoProto traceInfoProto = header.getTraceInfo();
+        if (traceInfoProto.hasSpanContext()) {
+          if (tracer == null) {
+            setTracer(Tracer.curThreadTracer());
+          }
+          if (tracer != null) {
+            // If the incoming RPC included tracing info, always continue the
+            // trace
+            SpanContext spanCtx = TraceUtils.byteStringToSpanContext(
+                traceInfoProto.getSpanContext());
+            if (spanCtx != null) {
+              span = tracer.newSpan(
+                  RpcClientUtil.toTraceName(rpcRequest.toString()), spanCtx);
+            }
+          }
         }
       }
 
@@ -2700,7 +2707,7 @@ private void processRpcRequest(RpcRequestHeaderProto header,
       RpcCall call = new RpcCall(this, header.getCallId(),
           header.getRetryCount(), rpcRequest,
           ProtoUtil.convert(header.getRpcKind()),
-          header.getClientId().toByteArray(), traceScope, callerContext);
+          header.getClientId().toByteArray(), span, callerContext);
 
       // Save the priority level assignment by the scheduler
       call.setPriorityLevel(callQueue.getPriorityLevel(call));
@@ -2953,10 +2960,9 @@ public void run() {
             LOG.debug(Thread.currentThread().getName() + ": " + call + " for RpcKind " + call.rpcKind);
           }
           CurCall.set(call);
-          if (call.traceScope != null) {
-            call.traceScope.reattach();
-            traceScope = call.traceScope;
-            traceScope.getSpan().addTimelineAnnotation("called");
+          if (call.span != null) {
+            traceScope = tracer.activateSpan(call.span);
+            call.span.addTimelineAnnotation("called");
           }
           // always update the current call context
           CallerContext.setCurrent(call.callerContext);
@@ -2971,14 +2977,14 @@ public void run() {
           if (running) {                          // unexpected -- log it
             LOG.info(Thread.currentThread().getName() + " unexpectedly interrupted", e);
             if (traceScope != null) {
-              traceScope.getSpan().addTimelineAnnotation("unexpectedly interrupted: " +
+              traceScope.addTimelineAnnotation("unexpectedly interrupted: " +
                   StringUtils.stringifyException(e));
             }
           }
         } catch (Exception e) {
           LOG.info(Thread.currentThread().getName() + " caught an exception", e);
           if (traceScope != null) {
-            traceScope.getSpan().addTimelineAnnotation("Exception: " +
+            traceScope.addTimelineAnnotation("Exception: " +
                 StringUtils.stringifyException(e));
           }
         } finally {

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/ipc/WritableRpcEngine.java

@@ -39,8 +39,8 @@
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.classification.InterfaceStability;
 import org.apache.hadoop.conf.*;
-import org.apache.htrace.core.TraceScope;
-import org.apache.htrace.core.Tracer;
+import org.apache.hadoop.tracing.TraceScope;
+import org.apache.hadoop.tracing.Tracer;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/security/Groups.java

@@ -34,8 +34,8 @@
 import java.util.concurrent.atomic.AtomicLong;
 import java.util.concurrent.atomic.AtomicReference;
 
-import org.apache.htrace.core.TraceScope;
-import org.apache.htrace.core.Tracer;
+import org.apache.hadoop.tracing.TraceScope;
+import org.apache.hadoop.tracing.Tracer;
 import org.apache.hadoop.thirdparty.com.google.common.annotations.VisibleForTesting;
 import org.apache.hadoop.thirdparty.com.google.common.base.Ticker;
 import org.apache.hadoop.thirdparty.com.google.common.cache.CacheBuilder;