From 13926c385c8ca606d9acd8a969a73dc29edd7413 Mon Sep 17 00:00:00 2001
From: Eric Holk <eholk@google.com>
Date: Mon, 9 Sep 2019 15:03:37 -0700
Subject: [PATCH 1/2] Add additional system_server benchmarks

This CL adds benchmarks for the following PackageManager APIs:
* getInstalledApplications
* getInstalledPackages
* getPackageInfo
* getApplicationInfo
* getResourcesForApplication
* getActivityInfo

Bug: 140743821
Change-Id: I467e4264a5e8f5c1c34194c7ad4b4c415387da9e
---
 .../src/SystemServerBenchmarkActivity.java    | 46 +++++++++++++++++++
 1 file changed, 46 insertions(+)

diff --git a/startop/apps/test/src/SystemServerBenchmarkActivity.java b/startop/apps/test/src/SystemServerBenchmarkActivity.java
index 59a30a540d999..c370924c943ca 100644
--- a/startop/apps/test/src/SystemServerBenchmarkActivity.java
+++ b/startop/apps/test/src/SystemServerBenchmarkActivity.java
@@ -17,8 +17,11 @@
 package com.android.startop.test;
 
 import android.app.Activity;
+import android.content.ComponentName;
 import android.content.Context;
+import android.content.pm.ApplicationInfo;
 import android.content.pm.PackageManager;
+import android.content.pm.PackageManager.NameNotFoundException;
 import android.os.AsyncTask;
 import android.os.Bundle;
 import android.os.Trace;
@@ -108,5 +111,48 @@ public class SystemServerBenchmarkActivity extends Activity {
         new Benchmark(benchmarkList, "getInstalledApplications", () -> {
             pm.getInstalledApplications(PackageManager.MATCH_SYSTEM_ONLY);
         });
+
+        new Benchmark(benchmarkList, "getInstalledPackages", () -> {
+            pm.getInstalledPackages(PackageManager.GET_ACTIVITIES);
+        });
+
+        new Benchmark(benchmarkList, "getPackageInfo", () -> {
+            try {
+                pm.getPackageInfo("com.android.startop.test", 0);
+            } catch (NameNotFoundException e) {
+                throw new RuntimeException(e);
+            }
+        });
+
+        new Benchmark(benchmarkList, "getApplicationInfo", () -> {
+            try {
+                pm.getApplicationInfo("com.android.startop.test", 0);
+            } catch (NameNotFoundException e) {
+                throw new RuntimeException(e);
+            }
+        });
+
+        try {
+            ApplicationInfo app = pm.getApplicationInfo("com.android.startop.test", 0);
+            new Benchmark(benchmarkList, "getResourcesForApplication", () -> {
+                try {
+                    pm.getResourcesForApplication(app);
+                } catch (NameNotFoundException e) {
+                    throw new RuntimeException(e);
+                }
+            });
+        } catch (NameNotFoundException e) {
+            throw new RuntimeException(e);
+        }
+
+        ComponentName component = new ComponentName(this, this.getClass());
+        new Benchmark(benchmarkList, "getActivityInfo", () -> {
+            try {
+                pm.getActivityInfo(component, PackageManager.GET_META_DATA);
+            } catch (NameNotFoundException e) {
+                throw new RuntimeException(e);
+            }
+        });
+
     }
 }

From 4777ee062110421089b8eb8bd64b383937cf1739 Mon Sep 17 00:00:00 2001
From: Eric Holk <eholk@google.com>
Date: Tue, 10 Sep 2019 14:22:12 -0700
Subject: [PATCH 2/2] Run system_server benchmarks for 5 seconds

Especially for short running methods, this gives us better results and also
gives us more data for things like simpleperf to work on.

Since we don't know ahead of time how many times each benchmark will run, we had
to switch the mean and standard deviation formulas to one that supports running
updates. This has the advantage of making it constant space.

Bug: 140743821
Change-Id: I3e6b6b44d3bd573bad8afc8831226194147b108a
---
 .../src/SystemServerBenchmarkActivity.java    | 36 +++++++++----------
 1 file changed, 17 insertions(+), 19 deletions(-)

diff --git a/startop/apps/test/src/SystemServerBenchmarkActivity.java b/startop/apps/test/src/SystemServerBenchmarkActivity.java
index c370924c943ca..61d43226c41ea 100644
--- a/startop/apps/test/src/SystemServerBenchmarkActivity.java
+++ b/startop/apps/test/src/SystemServerBenchmarkActivity.java
@@ -35,7 +35,8 @@ import android.widget.TextView;
 import java.util.Arrays;
 
 class Benchmark {
-    public static final int NUM_ITERATIONS = 1000;
+    // Time limit to run benchmarks in seconds
+    public static final int TIME_LIMIT = 5;
 
     public Benchmark(ViewGroup parent, CharSequence name, Runnable thunk) {
         Context context = parent.getContext();
@@ -57,28 +58,25 @@ class Benchmark {
 
                 @Override
                 protected Object doInBackground(Object... _args) {
-                    long[] results = new long[NUM_ITERATIONS];
+                    long startTime = System.nanoTime();
+                    int count = 0;
 
                     // Run benchmark
-                    for (int i = 0; i < results.length; i++) {
-                        results[i] = -System.nanoTime();
+                    while (true) {
+                        long elapsed = -System.nanoTime();
                         thunk.run();
-                        results[i] += System.nanoTime();
+                        elapsed += System.nanoTime();
+
+                        count++;
+                        double elapsedVariance = (double) elapsed - resultMean;
+                        resultMean += elapsedVariance / count;
+                        resultStdev += elapsedVariance * ((double) elapsed - resultMean);
+
+                        if (System.nanoTime() - startTime > TIME_LIMIT * 1e9) {
+                            break;
+                        }
                     }
-
-                    // Compute mean
-                    long sum = Arrays.stream(results).sum();
-                    resultMean = (double) sum / results.length;
-
-                    // Compute standard deviation
-                    double variance = 0;
-                    for (long i : results) {
-                        double t = (double) i - resultMean;
-                        variance += t * t;
-                    }
-                    variance /= results.length - 1;
-
-                    resultStdev = Math.sqrt(variance);
+                    resultStdev = Math.sqrt(resultStdev / (count - 1));
 
                     return null;
                 }