Profiler: split up writing into logical pieces.

As a side effect, we now write a whole counter series in one go, instead of having to fake TaskData for each data point.

This will allow us in the future to pass in multiple counter series in one go for stacked charts.

PiperOrigin-RevId: 496861570
Change-Id: I5e5725c22026419ab0cfb7764302393385becaeb

src/main/java/com/google/devtools/build/lib/profiler/BUILD

@@ -13,6 +13,7 @@ java_library(
     srcs = [
         "AutoProfiler.java",
         "CollectLocalResourceUsage.java",
+        "CounterSeriesTraceData.java",
         "JsonTraceFileWriter.java",
         "MemoryProfiler.java",
         "MetricData.java",
@@ -24,7 +25,9 @@ java_library(
         "SilentCloseable.java",
         "SingleStatRecorder.java",
         "StatRecorder.java",
+        "ThreadMetadata.java",
         "TimeSeries.java",
+        "TraceData.java",
     ],
     deps = [
         ":network_metrics_collector",

src/main/java/com/google/devtools/build/lib/profiler/CounterSeriesTraceData.java

@@ -0,0 +1,115 @@
+// Copyright 2022 The Bazel Authors. All rights reserved.
+//
+// Licensed 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 com.google.devtools.build.lib.profiler;
+
+import static java.util.Map.entry;
+
+import com.google.common.base.Preconditions;
+import com.google.common.collect.ImmutableMap;
+import com.google.gson.stream.JsonWriter;
+import java.io.IOException;
+import java.time.Duration;
+import java.util.concurrent.TimeUnit;
+import javax.annotation.Nullable;
+
+/**
+ * Used to inject a whole counter series in one go in the JSON trace profile; these could be used to
+ * represent CPU or memory usages over the course of an invocations (as opposed to individual tasks
+ * such as executing an action).
+ */
+final class CounterSeriesTraceData implements TraceData {
+  private final String shortName;
+  private final String readableName;
+  private final double[] counterValues;
+  private final Duration profileStart;
+  private final Duration bucketDuration;
+  @Nullable private final String colorName;
+
+  CounterSeriesTraceData(
+      ProfilerTask profilerTask,
+      double[] counterValues,
+      Duration profileStart,
+      Duration bucketDuration) {
+    Preconditions.checkArgument(COUNTER_TASK_TO_SERIES_NAME.containsKey(profilerTask));
+    this.shortName = profilerTask.description;
+    this.readableName = COUNTER_TASK_TO_SERIES_NAME.get(profilerTask);
+    this.counterValues = counterValues;
+    this.profileStart = profileStart;
+    this.bucketDuration = bucketDuration;
+
+    // Pick acceptable counter colors manually, unfortunately we have to pick from these
+    // weird reserved names from
+    // https://github.com/catapult-project/catapult/blob/master/tracing/tracing/base/color_scheme.html
+    this.colorName = COUNTER_TASK_TO_COLOR.get(profilerTask);
+  }
+
+  // Pick acceptable counter colors manually, unfortunately we have to pick from these
+  // weird reserved names from
+  // https://github.com/catapult-project/catapult/blob/master/tracing/tracing/base/color_scheme.html
+  private static final ImmutableMap<ProfilerTask, String> COUNTER_TASK_TO_COLOR =
+      ImmutableMap.ofEntries(
+          entry(ProfilerTask.LOCAL_CPU_USAGE, "good"),
+          entry(ProfilerTask.SYSTEM_CPU_USAGE, "rail_load"),
+          entry(ProfilerTask.LOCAL_MEMORY_USAGE, "olive"),
+          entry(ProfilerTask.SYSTEM_MEMORY_USAGE, "bad"),
+          entry(ProfilerTask.SYSTEM_NETWORK_UP_USAGE, "rail_response"),
+          entry(ProfilerTask.SYSTEM_NETWORK_DOWN_USAGE, "rail_response"),
+          entry(ProfilerTask.WORKERS_MEMORY_USAGE, "rail_animation"),
+          entry(ProfilerTask.SYSTEM_LOAD_AVERAGE, "generic_work"),
+          entry(ProfilerTask.MEMORY_USAGE_ESTIMATION, "rail_idle"),
+          entry(ProfilerTask.CPU_USAGE_ESTIMATION, "cq_build_attempt_passed"));
+
+  private static final ImmutableMap<ProfilerTask, String> COUNTER_TASK_TO_SERIES_NAME =
+      ImmutableMap.ofEntries(
+          entry(ProfilerTask.ACTION_COUNTS, "action"),
+          entry(ProfilerTask.LOCAL_CPU_USAGE, "cpu"),
+          entry(ProfilerTask.SYSTEM_CPU_USAGE, "system cpu"),
+          entry(ProfilerTask.LOCAL_MEMORY_USAGE, "memory"),
+          entry(ProfilerTask.SYSTEM_MEMORY_USAGE, "system memory"),
+          entry(ProfilerTask.SYSTEM_NETWORK_UP_USAGE, "system network up (Mbps)"),
+          entry(ProfilerTask.SYSTEM_NETWORK_DOWN_USAGE, "system network down (Mbps)"),
+          entry(ProfilerTask.WORKERS_MEMORY_USAGE, "workers memory"),
+          entry(ProfilerTask.SYSTEM_LOAD_AVERAGE, "load"),
+          entry(ProfilerTask.MEMORY_USAGE_ESTIMATION, "estimated memory"),
+          entry(ProfilerTask.CPU_USAGE_ESTIMATION, "estimated cpu"));
+
+  @Override
+  public void writeTraceData(JsonWriter jsonWriter, long profileStartTimeNanos) throws IOException {
+    // See https://docs.google.com/document/d/1CvAClvFfyA5R-PhYUmn5OOQtYMH4h6I0nSsKchNAySU/preview#heading=h.msg3086636uq
+    // for how counter series are represented in the Chrome Trace Event format.
+    for (int i = 0; i < counterValues.length; i++) {
+      long timeNanos = profileStart.plus(bucketDuration.multipliedBy(i)).toNanos();
+      // Skip counts equal to zero. They will show up as a thin line in the profile.
+      if (Math.abs(counterValues[i]) <= 0.00001) {
+        continue;
+      }
+      jsonWriter.setIndent("  ");
+      jsonWriter.beginObject();
+      jsonWriter.setIndent("");
+      jsonWriter.name("name").value(shortName);
+      if (colorName != null) {
+        jsonWriter.name("cname").value(colorName);
+      }
+      jsonWriter.name("ph").value("C");
+      jsonWriter.name("ts").value(TimeUnit.NANOSECONDS.toMicros(timeNanos - profileStartTimeNanos));
+      jsonWriter.name("args");
+
+      jsonWriter.beginObject();
+      jsonWriter.name(readableName).value(counterValues[i]);
+      jsonWriter.endObject();
+
+      jsonWriter.endObject();
+    }
+  }
+}