commit ca3749469ce52f740a0ac0d3e06d19d523434153
author ulfjack <ulfjack@google.com> Tue Jan 21 06:51:13 2020 -0800
committer Copybara-Service <copybara-worker@google.com> Tue Jan 21 06:52:10 2020 -0800
tree 39d1e90050fb67f1687bc0179cd4db7741b99d20
parent 773d6977721ab7191f4eeb47bfdcb66c57932d12

Increase default concurrency level for NestedSetBuilder

This should reduce lock contention if there are a lot of threads trying
to access the map concurrently. The increase in memory is probably
negligible.

PiperOrigin-RevId: 290734310

src/main/java/com/google/devtools/build/lib/collect/nestedset/NestedSetBuilder.java

diff --git a/src/main/java/com/google/devtools/build/lib/collect/nestedset/NestedSetBuilder.java b/src/main/java/com/google/devtools/build/lib/collect/nestedset/NestedSetBuilder.java
index 3cb388f..cb27452 100644
--- a/src/main/java/com/google/devtools/build/lib/collect/nestedset/NestedSetBuilder.java
+++ b/src/main/java/com/google/devtools/build/lib/collect/nestedset/NestedSetBuilder.java
@@ -199,7 +199,7 @@
   }
 
   private static final ConcurrentMap<ImmutableList<?>, NestedSet<?>> immutableListCache =
-      new MapMaker().weakKeys().makeMap();
+      new MapMaker().concurrencyLevel(16).weakKeys().makeMap();
 
   /**
    * Creates a nested set from a given list of items.