Remove the logging of GaugeMetadata based on AppStart

Author: tejasd

firebase-perf/src/main/java/com/google/firebase/perf/FirebasePerformance.java

@@ -188,7 +188,6 @@ public static FirebasePerformance getInstance() {
         .initialize(firebaseApp, firebaseInstallationsApi, transportFactoryProvider);
 
     Context appContext = firebaseApp.getApplicationContext();
-    // TODO(b/110178816): Explore moving off of main thread.
     mMetadataBundle = extractMetadata(appContext);
 
     remoteConfigManager.setFirebaseRemoteConfigProvider(firebaseRemoteConfigProvider);

firebase-perf/src/main/java/com/google/firebase/perf/session/SessionManager.java

@@ -75,20 +75,13 @@ public SessionManager(
    * (currently that is before onResume finishes) to ensure gauge collection starts on time.
    */
   public void setApplicationContext(final Context appContext) {
-    // Get PerfSession in main thread first, because it is possible that app changes fg/bg state
-    // which creates a new perfSession, before the following is executed in background thread
-    final PerfSession appStartSession = perfSession;
     // TODO(b/258263016): Migrate to go/firebase-android-executors
     @SuppressLint("ThreadPoolCreation")
     ExecutorService executorService = Executors.newSingleThreadExecutor();
     syncInitFuture =
         executorService.submit(
             () -> {
               gaugeManager.initializeGaugeMetadataManager(appContext);
-              if (appStartSession.isGaugeAndEventCollectionEnabled()) {
-                gaugeManager.logGaugeMetadata(
-                    appStartSession.sessionId(), ApplicationProcessState.FOREGROUND);
-              }
             });
   }
 
@@ -134,9 +127,6 @@ public void updatePerfSession(PerfSession perfSession) {
       }
     }
 
-    // Log the gauge metadata event if data collection is enabled.
-    logGaugeMetadataIfCollectionEnabled(appStateMonitor.getAppState());
-
     // Start of stop the gauge data collection.
     startOrStopCollectingGauges(appStateMonitor.getAppState());
   }
@@ -148,7 +138,6 @@ public void updatePerfSession(PerfSession perfSession) {
    * this does not reset the perfSession.
    */
   public void initializeGaugeCollection() {
-    logGaugeMetadataIfCollectionEnabled(ApplicationProcessState.FOREGROUND);
     startOrStopCollectingGauges(ApplicationProcessState.FOREGROUND);
   }
 
@@ -176,12 +165,6 @@ public void unregisterForSessionUpdates(WeakReference<SessionAwareObject> client
     }
   }
 
-  private void logGaugeMetadataIfCollectionEnabled(ApplicationProcessState appState) {
-    if (perfSession.isGaugeAndEventCollectionEnabled()) {
-      gaugeManager.logGaugeMetadata(perfSession.sessionId(), appState);
-    }
-  }
-
   private void startOrStopCollectingGauges(ApplicationProcessState appState) {
     if (perfSession.isGaugeAndEventCollectionEnabled()) {
       gaugeManager.startCollectingGauges(perfSession, appState);

firebase-perf/src/main/java/com/google/firebase/perf/session/gauges/GaugeManager.java

@@ -73,16 +73,16 @@ private GaugeManager() {
         TransportManager.getInstance(),
         ConfigResolver.getInstance(),
         null,
-        new Lazy<>(() -> new CpuGaugeCollector()),
-        new Lazy<>(() -> new MemoryGaugeCollector()));
+        new Lazy<>(CpuGaugeCollector::new),
+        new Lazy<>(MemoryGaugeCollector::new));
   }
 
   @VisibleForTesting
   GaugeManager(
       Lazy<ScheduledExecutorService> gaugeManagerExecutor,
       TransportManager transportManager,
       ConfigResolver configResolver,
-      GaugeMetadataManager gaugeMetadataManager,
+      @Nullable GaugeMetadataManager gaugeMetadataManager,
       Lazy<CpuGaugeCollector> cpuGaugeCollector,
       Lazy<MemoryGaugeCollector> memoryGaugeCollector) {
 
@@ -141,7 +141,7 @@ public void startCollectingGauges(
       gaugeManagerDataCollectionJob =
           gaugeManagerExecutor
               .get()
-              .scheduleAtFixedRate(
+              .scheduleWithFixedDelay(
                   () -> {
                     syncFlush(sessionIdForScheduledTask, applicationProcessStateForScheduledTask);
                   },

firebase-perf/src/main/java/com/google/firebase/perf/session/gauges/GaugeMetadataManager.java

@@ -22,6 +22,11 @@
 import com.google.firebase.perf.util.StorageUnit;
 import com.google.firebase.perf.util.Utils;
 import com.google.firebase.perf.v1.GaugeMetadata;
+import java.io.BufferedReader;
+import java.io.FileReader;
+import java.io.IOException;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
 
 /**
  * The {@code GaugeMetadataManager} class is responsible for collecting {@link GaugeMetadata}
@@ -68,4 +73,23 @@ public int getMaxEncouragedAppJavaHeapMemoryKb() {
   public int getDeviceRamSizeKb() {
     return Utils.saturatedIntCast(StorageUnit.BYTES.toKilobytes(memoryInfo.totalMem));
   }
+
+  /** Returns the total ram size of the device (in kilobytes) by reading the "proc/meminfo" file. */
+  @VisibleForTesting
+  int readTotalRAM(String procFileName) {
+    try (BufferedReader br = new BufferedReader(new FileReader(procFileName))) {
+      for (String s = br.readLine(); s != null; s = br.readLine()) {
+        if (s.startsWith("MemTotal")) {
+          Matcher m = Pattern.compile("\\d+").matcher(s);
+          return m.find() ? Integer.parseInt(m.group()) : 0;
+        }
+      }
+    } catch (IOException ioe) {
+      logger.warn("Unable to read '" + procFileName + "' file: " + ioe.getMessage());
+    } catch (NumberFormatException nfe) {
+      logger.warn("Unable to parse '" + procFileName + "' file: " + nfe.getMessage());
+    }
+
+    return 0;
+  }
 }