Commits on Feb 12, 2019

1. [runtime] Optionally preload all the assemblies from the apk …

   [Startup performance][0] commit dispensed with preloading of all assemblies from
   the APK since it's no longer needed by Xamarin.Android, thus improving the
   overall startup time. However, it turns out that some applications (especially
   those using Xamarin.Forms, but not only) rely on the fact that all the
   assemblies are loaded by the time the application code is called. They do it by
   calling `AppDomain.CurrentDomain.GetAssemblies()` and iterating over the
   returned array in order to load resources, inject dependencies etc. This is not
   a correct way to do it and nobody should rely on the `GetAssemblies()` call
   returning all the assemblies available, but since this is currently required by
   the aforementioned applications, we need to hurt performance and restore the
   preload behavior albeit this time making it optional.
   
   This commit implements the preload in a similar way as before, however this time
   it is controlled by MSBuild property `$(AndroidEnablePreloadAssemblies)`
   (which currently defaults to `true`) which the developer can set in their
   project file and thus control the runtime behavior.
   
   The commit also updates (courtesy of Jon Peppers @jonathanpeppers) the
   Xamarin.Forms performance integration app in Xamarin.Android tests to fail in
   case the assemblies are *not* preloaded. Currently, this application yields the
   following performance hit on Pixel 3 XL with the preload enabled:
   
       02-11 21:19:58.647 27410 27410 I monodroid-timing: Assembly load: FormsViewGroup.dll preloaded; elapsed: 0s:1::267136
       02-11 21:19:58.648 27410 27410 I monodroid-timing: Assembly load: Newtonsoft.Json.dll preloaded; elapsed: 0s:0::999584
       02-11 21:19:58.649 27410 27410 I monodroid-timing: Assembly load: Plugin.Connectivity.Abstractions.dll preloaded; elapsed: 0s:0::916459
       02-11 21:19:58.650 27410 27410 I monodroid-timing: Assembly load: Plugin.Connectivity.dll preloaded; elapsed: 0s:0::886146
       02-11 21:19:58.651 27410 27410 I monodroid-timing: Assembly load: Xamarin.Android.Arch.Core.Common.dll preloaded; elapsed: 0s:0::890208
       02-11 21:19:58.652 27410 27410 I monodroid-timing: Assembly load: Xamarin.Android.Arch.Lifecycle.Common.dll preloaded; elapsed: 0s:0::918229
       02-11 21:19:58.653 27410 27410 I monodroid-timing: Assembly load: Xamarin.Android.Arch.Lifecycle.Runtime.dll preloaded; elapsed: 0s:0::880833
       02-11 21:19:58.653 27410 27410 I monodroid-timing: Assembly load: Xamarin.Android.Support.Animated.Vector.Drawable.dll preloaded; elapsed: 0s:0::894323
       02-11 21:19:58.654 27410 27410 I monodroid-timing: Assembly load: Xamarin.Android.Support.Annotations.dll preloaded; elapsed: 0s:0::928177
       02-11 21:19:58.655 27410 27410 I monodroid-timing: Assembly load: Xamarin.Android.Support.Compat.dll preloaded; elapsed: 0s:0::941719
       02-11 21:19:58.656 27410 27410 I monodroid-timing: Assembly load: Xamarin.Android.Support.Core.UI.dll preloaded; elapsed: 0s:0::936563
       02-11 21:19:58.657 27410 27410 I monodroid-timing: Assembly load: Xamarin.Android.Support.Core.Utils.dll preloaded; elapsed: 0s:0::938594
       02-11 21:19:58.658 27410 27410 I monodroid-timing: Assembly load: Xamarin.Android.Support.Design.dll preloaded; elapsed: 0s:0::983334
       02-11 21:19:58.659 27410 27410 I monodroid-timing: Assembly load: Xamarin.Android.Support.Fragment.dll preloaded; elapsed: 0s:0::946042
       02-11 21:19:58.660 27410 27410 I monodroid-timing: Assembly load: Xamarin.Android.Support.Media.Compat.dll preloaded; elapsed: 0s:0::927604
       02-11 21:19:58.661 27410 27410 I monodroid-timing: Assembly load: Xamarin.Android.Support.Transition.dll preloaded; elapsed: 0s:0::959376
       02-11 21:19:58.662 27410 27410 I monodroid-timing: Assembly load: Xamarin.Android.Support.v4.dll preloaded; elapsed: 0s:0::923750
       02-11 21:19:58.663 27410 27410 I monodroid-timing: Assembly load: Xamarin.Android.Support.v7.AppCompat.dll preloaded; elapsed: 0s:1::82500
       02-11 21:19:58.664 27410 27410 I monodroid-timing: Assembly load: Xamarin.Android.Support.v7.CardView.dll preloaded; elapsed: 0s:0::920313
       02-11 21:19:58.665 27410 27410 I monodroid-timing: Assembly load: Xamarin.Android.Support.v7.MediaRouter.dll preloaded; elapsed: 0s:0::949323
       02-11 21:19:58.666 27410 27410 I monodroid-timing: Assembly load: Xamarin.Android.Support.v7.Palette.dll preloaded; elapsed: 0s:0::906093
       02-11 21:19:58.667 27410 27410 I monodroid-timing: Assembly load: Xamarin.Android.Support.v7.RecyclerView.dll preloaded; elapsed: 0s:0::900782
       02-11 21:19:58.668 27410 27410 I monodroid-timing: Assembly load: Xamarin.Android.Support.Vector.Drawable.dll preloaded; elapsed: 0s:0::960416
       02-11 21:19:58.669 27410 27410 I monodroid-timing: Assembly load: Xamarin.Forms.Core.dll preloaded; elapsed: 0s:0::972396
       02-11 21:19:58.670 27410 27410 I monodroid-timing: Assembly load: Xamarin.Forms.Performance.Integration.dll preloaded; elapsed: 0s:0::898646
       02-11 21:19:58.671 27410 27410 I monodroid-timing: Assembly load: Xamarin.Forms.Platform.Android.dll preloaded; elapsed: 0s:0::932813
       02-11 21:19:58.672 27410 27410 I monodroid-timing: Assembly load: Xamarin.Forms.Platform.dll preloaded; elapsed: 0s:0::935677
       02-11 21:19:58.673 27410 27410 I monodroid-timing: Assembly load: Xamarin.Forms.Xaml.dll preloaded; elapsed: 0s:0::928594
       02-11 21:19:58.673 27410 27410 I monodroid-timing: Assembly load: preloaded 29 assemblies; elapsed: 0s:26::783805
   
   [0]: b90d3ab

   

   grendello committed Feb 12, 2019
   Configuration menu

   • View commit details
   • Copy full SHA for e230162
   • Browse repository at this point

   Copy the full SHA

   e230162 View commit details

   Browse the repository at this point in the history

2. Clarify the AndroidEnablePreloadAssemblies docs

   

   jonpryor committed Feb 12, 2019
   Configuration menu

   • View commit details
   • Copy full SHA for 69aad59
   • Browse repository at this point

   Copy the full SHA

   69aad59 View commit details

   Browse the repository at this point in the history