Make classes visibly initialized in bigger batches.

Change the batch size from 16 to 48. This should make app
startup faster for apps that initialize a lot of classes.

Test: m test-art-host-gtest
Test: testrunner.py --host --optimizing
Bug: 38383823
Change-Id: If6387dab27887b7380e30ee6e8b3376158ff04de

1 files changed, 7 insertions, 1 deletions

diff --git a/runtime/class_linker.cc b/runtime/class_linker.cc
index a2d07a5a7e..b98f704af3 100644
--- a/runtime/class_linker.cc
+++ b/runtime/class_linker.cc
@@ -299,7 +299,13 @@ class ClassLinker::VisiblyInitializedCallback final
     }
   }
 
-  static constexpr size_t kMaxClasses = 16;
+  // Making classes initialized in bigger batches helps with app startup for
+  // apps that initialize a lot of classes by running fewer checkpoints.
+  // (On the other hand, bigger batches make class initialization checks more
+  // likely to take a slow path but that is mitigated by making partially
+  // filled buffers visibly initialized if we take the slow path many times.
+  // See `Thread::kMakeVisiblyInitializedCounterTriggerCount`.)
+  static constexpr size_t kMaxClasses = 48;
 
   ClassLinker* const class_linker_;
   size_t num_classes_;