Refactor SkylarkStatistics to reduce size.

Does not save all Tasks anymore and generates TasksStatistics on the fly.
Adds an ArrayList implementation for primitive longs to efficiently save a lot
of task duration data. Necessary when loading lots of profile files.

--
MOS_MIGRATED_REVID=104656311

1 files changed, 36 insertions, 29 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/profiler/statistics/TasksStatistics.java b/src/main/java/com/google/devtools/build/lib/profiler/statistics/TasksStatistics.java
index 72afab45bf..2b60eb73e8 100644
--- a/src/main/java/com/google/devtools/build/lib/profiler/statistics/TasksStatistics.java
+++ b/src/main/java/com/google/devtools/build/lib/profiler/statistics/TasksStatistics.java
@@ -13,9 +13,8 @@
 // limitations under the License.
 package com.google.devtools.build.lib.profiler.statistics;
 
-import com.google.devtools.build.lib.profiler.ProfileInfo;
 import com.google.devtools.build.lib.profiler.ProfileInfo.Task;
-
+import com.google.devtools.build.lib.util.LongArrayList;
 import java.util.List;
 
 /**
@@ -32,7 +31,6 @@ public class TasksStatistics {
    */
   public final double standardDeviationMillis;
   public final long totalNanos;
-  public final long selfNanos;
 
   public TasksStatistics(
       String name,
@@ -41,8 +39,7 @@ public class TasksStatistics {
       long maxNanos,
       double medianNanos,
       double standardDeviationMillis,
-      long totalNanos,
-      long selfNanos) {
+      long totalNanos) {
     this.name = name;
     this.count = count;
     this.minNanos = minNanos;
@@ -50,7 +47,6 @@ public class TasksStatistics {
     this.medianNanos = medianNanos;
     this.standardDeviationMillis = standardDeviationMillis;
     this.totalNanos = totalNanos;
-    this.selfNanos = selfNanos;
   }
 
   public double minimumMillis() {
@@ -77,44 +73,55 @@ public class TasksStatistics {
     return toMilliSeconds(totalNanos);
   }
 
-  public double selfMillis() {
-    return toMilliSeconds(selfNanos);
-  }
-
-  public double selfMeanNanos() {
-    return selfNanos / count;
-  }
-
-  public double selfMeanMillis() {
-    return toMilliSeconds(selfMeanNanos());
+  @Override
+  public String toString() {
+    return String.format(
+        "%s %d %.3f %.3f %.3f %.3f %.3f %.3f",
+        name,
+        count,
+        minimumMillis(),
+        meanMillis(),
+        medianMillis(),
+        maximumMillis(),
+        standardDeviationMillis,
+        totalMillis());
   }
 
   /**
    * @return The set of statistics grouped in this class, computed from a list of {@link Task}s.
    */
   public static TasksStatistics create(String name, List<Task> tasks) {
-    tasks = ProfileInfo.TASK_DURATION_ORDERING.immutableSortedCopy(tasks);
-    int count = tasks.size();
-    long min = tasks.get(0).durationNanos;
-    long max = tasks.get(count - 1).durationNanos;
+    LongArrayList durations = new LongArrayList(tasks.size());
+    for (Task task : tasks) {
+      durations.add(task.durationNanos);
+    }
+    return create(name, durations);
+  }
+
+  /**
+   * @return The set of statistics grouped in this class, computed from a list of durations
+   */
+  public static TasksStatistics create(String name, LongArrayList durations) {
+    durations.sort();
+    int count = durations.size();
+    long min = durations.get(0);
+    long max = durations.get(count - 1);
 
     int midIndex = count / 2;
     double median =
-        tasks.size() % 2 == 0
-            ? (tasks.get(midIndex).durationNanos + tasks.get(midIndex - 1).durationNanos) / 2.0
-            : tasks.get(midIndex).durationNanos;
+        count % 2 == 0
+            ? (durations.get(midIndex) + durations.get(midIndex - 1)) / 2.0
+            : durations.get(midIndex);
 
     // Compute standard deviation with a shift to avoid catastrophic cancellation
     // and also do it in milliseconds, as in nanoseconds it overflows
     long sum = 0L;
-    long self = 0L;
     double sumOfSquaredShiftedMillis = 0L;
     final long shift = min;
 
-    for (Task task : tasks) {
-      sum += task.durationNanos;
-      self += task.durationNanos - task.getInheritedDuration();
-      double taskDurationShiftMillis = toMilliSeconds(task.durationNanos - shift);
+    for (int index = 0; index < count; index++) {
+      sum += durations.get(index);
+      double taskDurationShiftMillis = toMilliSeconds(durations.get(index) - shift);
       sumOfSquaredShiftedMillis += taskDurationShiftMillis * taskDurationShiftMillis;
     }
     double sumShiftedMillis = toMilliSeconds(sum - count * shift);
@@ -123,7 +130,7 @@ public class TasksStatistics {
         Math.sqrt(
             (sumOfSquaredShiftedMillis - (sumShiftedMillis * sumShiftedMillis) / count) / count);
 
-    return new TasksStatistics(name, count, min, max, median, standardDeviation, sum, self);
+    return new TasksStatistics(name, count, min, max, median, standardDeviation, sum);
   }
 
   static double toMilliSeconds(double nanoseconds) {