From d3501d8325e7ea054f06cd218fb3d182ca0ead13 Mon Sep 17 00:00:00 2001
From: Googler <noreply@google.com>
Date: Wed, 15 Aug 2018 13:39:01 -0700
Subject: Use ConcurrentHashMap instead of Cache where we aren't using any of
 the LoadingCache's capabilities. According to profiles, using
 ConcurrentHashMap is about 3x more efficient.

RELNOTES: None
PiperOrigin-RevId: 208874176
---
 .../devtools/build/lib/skyframe/GlobFunction.java  |  6 ++---
 .../google/devtools/build/lib/vfs/UnixGlob.java    | 27 +++++++---------------
 2 files changed, 10 insertions(+), 23 deletions(-)

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/GlobFunction.java b/src/main/java/com/google/devtools/build/lib/skyframe/GlobFunction.java
index 9d2c94ac8f..5820ac8e70 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/GlobFunction.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/GlobFunction.java
@@ -14,8 +14,6 @@
 package com.google.devtools.build.lib.skyframe;
 
 import com.google.common.base.Preconditions;
-import com.google.common.cache.Cache;
-import com.google.common.cache.CacheBuilder;
 import com.google.common.collect.Maps;
 import com.google.common.collect.Sets;
 import com.google.devtools.build.lib.actions.FileValue;
@@ -33,6 +31,7 @@ import com.google.devtools.build.skyframe.SkyFunctionException.Transience;
 import com.google.devtools.build.skyframe.SkyKey;
 import com.google.devtools.build.skyframe.SkyValue;
 import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
 import java.util.regex.Pattern;
 import javax.annotation.Nullable;
 
@@ -43,8 +42,7 @@ import javax.annotation.Nullable;
  */
 public final class GlobFunction implements SkyFunction {
 
-  private final Cache<String, Pattern> regexPatternCache =
-      CacheBuilder.newBuilder().maximumSize(10000).concurrencyLevel(4).build();
+  private final ConcurrentHashMap<String, Pattern> regexPatternCache = new ConcurrentHashMap<>();
 
   private final boolean alwaysUseDirListing;
 
diff --git a/src/main/java/com/google/devtools/build/lib/vfs/UnixGlob.java b/src/main/java/com/google/devtools/build/lib/vfs/UnixGlob.java
index ab421f218c..36273a2cc8 100644
--- a/src/main/java/com/google/devtools/build/lib/vfs/UnixGlob.java
+++ b/src/main/java/com/google/devtools/build/lib/vfs/UnixGlob.java
@@ -21,9 +21,6 @@ import com.google.common.base.Predicate;
 import com.google.common.base.Predicates;
 import com.google.common.base.Splitter;
 import com.google.common.base.Throwables;
-import com.google.common.cache.Cache;
-import com.google.common.cache.CacheBuilder;
-import com.google.common.cache.CacheLoader;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Iterables;
 import com.google.common.collect.Lists;
@@ -42,6 +39,7 @@ import java.util.Collections;
 import java.util.List;
 import java.util.Objects;
 import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.Future;
 import java.util.concurrent.ThreadPoolExecutor;
@@ -148,7 +146,7 @@ public final class UnixGlob {
   }
 
   /**
-   * Calls {@link #matches(String, String, Cache) matches(pattern, str, null)}
+   * Calls {@link #matches(String, String, ConcurrentHashMap) matches(pattern, str, null)}
    */
   public static boolean matches(String pattern, String str) {
     return matches(pattern, str, null);
@@ -164,7 +162,7 @@ public final class UnixGlob {
    *        {@code null} to skip caching
    */
   public static boolean matches(String pattern, String str,
-      Cache<String, Pattern> patternCache) {
+      ConcurrentHashMap<String, Pattern> patternCache) {
     if (pattern.length() == 0 || str.length() == 0) {
       return false;
     }
@@ -196,13 +194,10 @@ public final class UnixGlob {
       return str.startsWith(pattern.substring(0, lastIndex));
     }
 
-    Pattern regex = patternCache == null ? null : patternCache.getIfPresent(pattern);
-    if (regex == null) {
-      regex = makePatternFromWildcard(pattern);
-      if (patternCache != null) {
-        patternCache.put(pattern, regex);
-      }
-    }
+    Pattern regex =
+        patternCache == null
+            ? makePatternFromWildcard(pattern)
+            : patternCache.computeIfAbsent(pattern, p -> makePatternFromWildcard(p));
     return regex.matcher(str).matches();
   }
 
@@ -477,13 +472,7 @@ public final class UnixGlob {
   private static final class GlobVisitor {
     // These collections are used across workers and must therefore be thread-safe.
     private final Collection<Path> results = Sets.newConcurrentHashSet();
-    private final Cache<String, Pattern> cache = CacheBuilder.newBuilder().build(
-        new CacheLoader<String, Pattern>() {
-            @Override
-            public Pattern load(String wildcard) {
-              return makePatternFromWildcard(wildcard);
-            }
-          });
+    private final ConcurrentHashMap<String, Pattern> cache = new ConcurrentHashMap<>();
 
     private final GlobFuture result;
     private final ThreadPoolExecutor executor;
-- 
cgit v1.2.3