Installing app takes minutes with dex2oat warnings

Question

I have re-opened an Android Studio project after quite some time, and I'm seeing fast builds as usual, but now the "Install" step from Android Studio (3.5) is taking minutes, while it used to take seconds.

If I open the device Logcat while installing, I can see a huge amount of these:

W/dex2oat: Method processed more than once: void com.package.base.view.BaseDialog.onSaveInstanceState(android.os.Bundle)
W/dex2oat: Method processed more than once: void com.package.base.view.BaseDialog.onViewCreated(android.view.View, android.os.Bundle)
W/dex2oat: Method processed more than once: void com.package.base.view.BaseDialog.onViewModelCreated()
W/dex2oat: Method processed more than once: void com.package.base.view.BaseDialog.removeCancelListener(com.package.base.view.BaseDialog$CancelListener)
W/dex2oat: Method processed more than once: void com.package.base.view.BaseDialog.removeDismissListener(com.package.base.view.BaseDialog$DismissListener)
W/dex2oat: Method processed more than once: void com.package.base.view.BaseDialog.setChildFragmentInjector(dagger.android.DispatchingAndroidInjector)
W/dex2oat: Method processed more than once: void com.package.base.view.BaseDialog.setSharedValue(java.lang.String, java.lang.Object)
W/dex2oat: Method processed more than once: void com.package.base.view.BaseDialog.setViewModelFactory(androidx.lifecycle.ViewModelProvider$Factory)
W/dex2oat: Method processed more than once: dagger.android.AndroidInjector com.package.base.view.BaseDialog.supportFragmentInjector()
I/dex2oat: Explicit concurrent copying GC freed 647(112KB) AllocSpace objects, 0(0B) LOS objects, 32% free, 12MB/18MB, paused 60us total 250.774ms
I/dex2oat: Explicit concurrent copying GC freed 446(29KB) AllocSpace objects, 0(0B) LOS objects, 32% free, 12MB/18MB, paused 60us total 252.704ms
I/dex2oat: Explicit concurrent copying GC freed 396(13KB) AllocSpace objects, 0(0B) LOS objects, 32% free, 12MB/18MB, paused 67us total 257.367ms
I/dex2oat: Explicit concurrent copying GC freed 413(13KB) AllocSpace objects, 0(0B) LOS objects, 32% free, 12MB/18MB, paused 68us total 258.540ms
I/dex2oat: Explicit concurrent copying GC freed 413(13KB) AllocSpace objects, 0(0B) LOS objects, 32% free, 12MB/18MB, paused 64us total 253.988ms
I/dex2oat: Explicit concurrent copying GC freed 413(13KB) AllocSpace objects, 0(0B) LOS objects, 32% free, 12MB/18MB, paused 61us total 258.701ms
I/dex2oat: Explicit concurrent copying GC freed 413(13KB) AllocSpace objects, 0(0B) LOS objects, 32% free, 12MB/18MB, paused 60us total 255.313ms
I/dex2oat: Explicit concurrent copying GC freed 419(45KB) AllocSpace objects, 0(0B) LOS objects, 32% free, 12MB/18MB, paused 60us total 261.034ms
W/dex2oat: Method processed more than once: void com.package.base.view.BaseFragment.<init>()
W/dex2oat: Method processed more than once: void com.package.base.view.BaseFragment.applyStatusBar(com.package.base.view.BaseFragment$StatusBar)
W/dex2oat: Method processed more than once: void com.package.base.view.BaseFragment.dispatchOnStatusBar()
W/dex2oat: Method processed more than once: void com.package.base.view.BaseFragment.restoreStatusBar(android.app.Activity)
W/dex2oat: Method processed more than once: void com.package.base.view.BaseFragment.saveStatusBar(android.app.Activity)

All methods seem to be processed twice (at least) and the garbage collector seems to be doing a lot of work.

I don't know what happened, but I would love to have this fast as it was - right now developing is impossible. Can anyone help?

Extra info

Before dex2oat starts this very long process, I can see the following logs:

W/dex2oat: Unexpected CPU variant for X86 using defaults: x86
W/dex2oat: Mismatch between dex2oat instruction set features (ISA: X86 Feature string: -ssse3,-sse4.1,-sse4.2,-avx,-avx2,-popcnt) and those of dex2oat executable (ISA: X86 Feature string: ssse3,-sse4.1,-sse4.2,-avx,-avx2,-popcnt) for the command line:
W/dex2oat: /system/bin/dex2oat --zip-fd=8 --zip-location=base.apk --input-vdex-fd=-1 --output-vdex-fd=10 --oat-fd=9 --oat-location=/data/app/com.package-7KbZxh8JQyXUOcSGvv-5hA==/oat/x86/base.odex --instruction-set=x86 --instruction-set-variant=x86 --instruction-set-features=default --runtime-arg -Xms64m --runtime-arg -Xmx512m --compiler-filter=quicken --swap-fd=11 --debuggable --classpath-dir=/data/app/com.package-7KbZxh8JQyXUOcSGvv-5hA== --class-loader-context=PCL[]
I/dex2oat: /system/bin/dex2oat --input-vdex-fd=-1 --output-vdex-fd=10 --compiler-filter=quicken --debuggable --classpath-dir=/data/app/com.package-7KbZxh8JQyXUOcSGvv-5hA== --class-loader-context=PCL[]
I/dex2oat: Large app, accepted running with swap.

Build file

This is part of build.gradle for the app module. This is a multi-module project, but the other files are very similar.

android {

    compileSdkVersion(AndroidBuild.compileSdk)

    defaultConfig {
        applicationId = "com.package"
        minSdkVersion(AndroidBuild.minSdk)
        targetSdkVersion(AndroidBuild.targetSdk)
        versionCode = 7
        versionName = "0.2.0"
        vectorDrawables.useSupportLibrary = true
        renderscriptTargetApi = 24
        renderscriptSupportModeEnabled = true
        multiDexEnabled = true

        testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
        testInstrumentationRunnerArgument("clearPackageData", "true")
    }

    signingConfigs {
        create("release") {
            // signing stuff
        }
    }

    testOptions {
        // execution = "ANDROIDX_TEST_ORCHESTRATOR"
    }

    buildTypes {
        getByName("release") {
            signingConfig = signingConfigs.getByName("release")
            isShrinkResources = true
            isMinifyEnabled = true
            proguardFile(getDefaultProguardFile("proguard-defaults.txt"))
            proguardFile("proguard-rules.pro")
        }
        getByName("debug") {
            versionNameSuffix = "-debug"
            // Hoping that this should speed up builds due to multidexing
            defaultConfig.minSdkVersion(21)
        }
    }

    dataBinding.isEnabled = true
    compileOptions {
        sourceCompatibility = JavaVersion.VERSION_1_8
        targetCompatibility = JavaVersion.VERSION_1_8
    }
}

aapt output when using vmSafeMode="true"

Output when running ./Library/Android/sdk/build-tools/29.0.2/aapt list -a app-debug.apk is huge, pasting only the relevant part:

E: application (line=57)
  A: android:theme(0x01010000)=@0x7f11014c
  A: android:label(0x01010001)=@0x7f100002
  A: android:icon(0x01010002)=@0x7f0e0001
  A: android:name(0x01010003)="com.package.App" (Raw: "com.package.App")
  A: android:debuggable(0x0101000f)=(type 0x12)0xffffffff
  A: android:allowBackup(0x01010280)=(type 0x12)0xffffffff
  A: android:vmSafeMode(0x010102b8)=(type 0x12)0xffffffff
  A: android:supportsRtl(0x010103af)=(type 0x12)0xffffffff
  A: android:appComponentFactory(0x0101057a)="androidx.core.app.CoreComponentFactory" (Raw: "androidx.core.app.CoreComponentFactory")

Answer 1

Intro

On device cache build at install time (using dex2oat) i.e. after the app has been built on your build machine:

dex2oat warnings

This is where the W/dex2oat: Method processed more than once: warnings are coming from in the android.googlesource in the file verification_results.cc method WriterMutexLock mu().

  WriterMutexLock mu(Thread::Current(), verified_methods_lock_);
  auto it = verified_methods_.find(ref);
  if (it != verified_methods_.end()) {
    // TODO: Investigate why are we doing the work again for this method and try to avoid it.
    LOG(WARNING) << "Method processed more than once: " << ref.PrettyMethod();
    if (!Runtime::Current()->UseJitCompilation()) {
      DCHECK_EQ(it->second->GetDevirtMap().size(), verified_method->GetDevirtMap().size());
      DCHECK_EQ(it->second->GetSafeCastSet().size(), verified_method->GetSafeCastSet().size());
    }
    // Delete the new verified method since there was already an existing one registered. It
    // is unsafe to replace the existing one since the JIT may be using it to generate a
    // native GC map.
    delete verified_method;
    return;
  }

The:

// TODO: Investigate why are we doing the work again for this method and try to avoid it.

is interesting, seems Google know about it, somewhat.

This Info message is also interesting:

I/dex2oat: Large app, accepted running with swap.

This suggests the dex2oat has detected a large app, and is going to swap (swapping is VERY slow, RAM copied to storage, and back again).

Fixes

(1) Reduce app size

Slim down your app! See Reduce your app size.

(2) Disable ART

ref1 Create a new minimal …/app/src/debug/AndroidManifest.xml file:

<manifest
 xmlns:android="http://schemas.android.com/apk/res/android"> 
 <application android:vmSafeMode="true" />
</manifest>

ref2 android:vmSafeMode

Indicates whether the app would like the virtual machine (VM) to operate in safe mode. The default value is "false".

This attribute was added in API level 8 where a value of "true" disabled the Dalvik just-in-time (JIT) compiler.

This attribute was adapted in API level 22 where a value of "true" disabled the ART ahead-of-time (AOT) compiler. When vmSafeMode is set to true this process will be executed with the following argument:

(3) Late manual argument insertion with adb shell:

/system/bin/dex2oat ... --compiler-filter=interpret-only

Your running:

 /system/bin/dex2oat --zip-fd=8 --zip-location=base.apk --input-vdex-fd=-1 --output-vdex-fd=10 --oat-fd=9 --oat-location=/data/app/com.package-7KbZxh8JQyXUOcSGvv-5hA==/oat/x86/base.odex --instruction-set=x86 --instruction-set-variant=x86 --instruction-set-features=default --runtime-arg -Xms64m --runtime-arg -Xmx512m --compiler-filter=quicken --swap-fd=11 --debuggable --classpath-dir=/data/app/com.package-7KbZxh8JQyXUOcSGvv-5hA== --class-loader-context=PCL[]

and:

 /system/bin/dex2oat --input-vdex-fd=-1 --output-vdex-fd=10 --compiler-filter=quicken --debuggable --classpath-dir=/data/app/com.package-7KbZxh8JQyXUOcSGvv-5hA== --class-loader-context=PCL[]

(4) Remove tasks

Try to maximise your available RAM at install time by closing unneeded apps (or use something like Greenify).

(5) Try useing Instant run

• Build and deploy only the incremental changes
• Don’t reinstall the app.
• Don’t restart the app.
• Don’t even restart the Activity.

Debugging

Another method for determining if vmSafeMode is set for a given APK is to use the aapt.exe tool. You will find the aapt tool in the build-tools folder of the Android SDK, which differs in location based on your chosen OS. You will probably have several different versions installed and will find it in a location such as:

.../Android/sdk/build-tools/22.0.1/aapt.exe

Execute the list command:

aapt list -a myapkfile.apk

This should produce output including:

Android manifest:
N: android=http://schemas.android.com/apk/res/android
  E: manifest (line=17)
    A: android:versionCode(0x0101021b)=(type 0x10)0x1
    A: android:versionName(0x0101021c)="1.0" (Raw: "1.0")
    A: package="com.testing.sample.myapp" (Raw: "com.testing.sample.myapp")
    A: platformBuildVersionCode=(type 0x10)0x16 (Raw: "22")         <---NOTE
    A: platformBuildVersionName="5.1.1-1819727" (Raw: "5.1.1-1819727")
    E: uses-sdk (line=22)
      A: android:minSdkVersion(0x0101020c)=(type 0x10)0x15
      A: android:targetSdkVersion(0x01010270)=(type 0x10)0x16
    E: application (line=26)
      A: android:label(0x01010001)=@0x7f0b0001
      A: android:icon(0x01010002)=@0x7f030000
      A: android:debuggable(0x0101000f)=(type 0x12)0xffffffff
      A: android:vmSafeMode(0x010102b8)=(type 0x12)0xffffffff
                       ^
                       |
----------NOTE---------+

Answer 2

First of all what is dex2oat, it works for Verifying app behavior on the Android runtime (ART) for this refer this link

https://developer.android.com/guide/practices/verifying-apps-art

Now as you need to do is to make this process faster for builds

you can disable this ART(ahead-of-time) to optimize debug deployment and make faster builds. by

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
   ...>

 <application
 ...
 android:vmSafeMode="true">
 ...

Note: it is only possible for targetSdkVersion of 22+ and you’re running a device using the ART runtime.

after disabling this it will decrease you build time for more you can refere the following link https://androidbycode.wordpress.com/2015/07/03/disable-android-art-ahead-of-time-compilation-to-optimize-debug-deployment/

Answer 3

I have something that can help you if you are using windows open up terminal window in android studio and type

gradlew installDebug

or in linux put

./gradlew installDebug 

for more info link here

https://developer.android.com/studio/build/building-cmdline

Answer 4

Below adjustments could make things faster (I have 8Go ram, adapt to yours):

In ..\android-studio\bin\studio64.exe.vmoptions

-Xms2G
-Xmx4G
-XX:ReservedCodeCacheSize=580m
-XX:MetaspaceSize=512m

In studio.exe.vmoptions

-server
-Xms1G
-Xmx2G
-XX:ReservedCodeCacheSize=480m