Merge "Add support for ICU data pinning in the Zygote"

1 files changed, 30 insertions, 0 deletions

diff --git a/core/java/com/android/internal/os/ZygoteInit.java b/core/java/com/android/internal/os/ZygoteInit.java
index 1440e5fb559d..83ffb54af583 100644
--- a/core/java/com/android/internal/os/ZygoteInit.java
+++ b/core/java/com/android/internal/os/ZygoteInit.java
@@ -22,6 +22,9 @@ import static android.system.OsConstants.S_IRWXO;
 
 import android.content.res.Resources;
 import android.content.res.TypedArray;
+import android.icu.impl.CacheValue;
+import android.icu.text.DecimalFormatSymbols;
+import android.icu.util.ULocale;
 import android.net.LocalServerSocket;
 import android.opengl.EGL14;
 import android.os.Process;
@@ -181,6 +184,9 @@ public class ZygoteInit {
 
     static void preload() {
         Log.d(TAG, "begin preload");
+        Trace.traceBegin(Trace.TRACE_TAG_DALVIK, "BeginIcuCachePinning");
+        beginIcuCachePinning();
+        Trace.traceEnd(Trace.TRACE_TAG_DALVIK);
         Trace.traceBegin(Trace.TRACE_TAG_DALVIK, "PreloadClasses");
         preloadClasses();
         Trace.traceEnd(Trace.TRACE_TAG_DALVIK);
@@ -195,10 +201,34 @@ public class ZygoteInit {
         // Ask the WebViewFactory to do any initialization that must run in the zygote process,
         // for memory sharing purposes.
         WebViewFactory.prepareWebViewInZygote();
+        endIcuCachePinning();
         warmUpJcaProviders();
         Log.d(TAG, "end preload");
     }
 
+    private static void beginIcuCachePinning() {
+        // Pin ICU data in memory from this point that would normally be held by soft references.
+        // Without this, any references created immediately below or during class preloading
+        // would be collected when the Zygote GC runs in gcAndFinalize().
+        Log.i(TAG, "Installing ICU cache reference pinning...");
+
+        CacheValue.setStrength(CacheValue.Strength.STRONG);
+
+        Log.i(TAG, "Preloading ICU data...");
+        // Explicitly exercise code to cache data apps are likely to need.
+        ULocale[] localesToPin = { ULocale.ROOT, ULocale.US, ULocale.getDefault() };
+        for (ULocale uLocale : localesToPin) {
+            new DecimalFormatSymbols(uLocale);
+        }
+    }
+
+    private static void endIcuCachePinning() {
+        // All cache references created by ICU from this point will be soft.
+        CacheValue.setStrength(CacheValue.Strength.SOFT);
+
+        Log.i(TAG, "Uninstalled ICU cache reference pinning...");
+    }
+
     private static void preloadSharedLibraries() {
         Log.i(TAG, "Preloading shared libraries...");
         System.loadLibrary("android");