blob: a353d28668f64e2bc9cf9bf1063d6d221e887c2d [file] [log] [blame]
// Copyright 2017 The Bazel Authors. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package com.google.devtools.build.lib.runtime;
import com.github.benmanes.caffeine.cache.stats.CacheStats;
import com.google.common.base.Preconditions;
import com.google.common.flogger.GoogleLogger;
import com.google.devtools.build.lib.buildtool.BuildRequest;
import com.google.devtools.build.lib.exec.ExecutionOptions;
import com.google.devtools.build.lib.exec.ExecutorBuilder;
import com.google.devtools.build.lib.vfs.DigestUtils;
/** Enables the caching of file digests in {@link DigestUtils}. */
public class CacheFileDigestsModule extends BlazeModule {
private static final GoogleLogger logger = GoogleLogger.forEnclosingClass();
/** Stats gathered at the beginning of a command, to compute deltas on completion. */
private CacheStats stats;
/**
* Last known size of the cache. Changes to this value cause the cache to be reinitialized. null
* if we don't know anything about the last value yet (i.e. before any command has been run).
*/
private Long lastKnownCacheSize;
public CacheFileDigestsModule() {}
/**
* Adds a line to the log with cache statistics.
*
* @param message message to prefix to the written line
* @param stats the cache statistics to be logged
*/
private static void logStats(String message, CacheStats stats) {
logger.atInfo().log(
"%s: hit count=%d, miss count=%d, hit rate=%g, eviction count=%d",
message, stats.hitCount(), stats.missCount(), stats.hitRate(), stats.evictionCount());
}
@Override
public void executorInit(CommandEnvironment env, BuildRequest request, ExecutorBuilder builder) {
ExecutionOptions options = request.getOptions(ExecutionOptions.class);
if (lastKnownCacheSize == null
|| options.cacheSizeForComputedFileDigests != lastKnownCacheSize) {
logger.atInfo().log(
"Reconfiguring cache with size=%d", options.cacheSizeForComputedFileDigests);
DigestUtils.configureCache(options.cacheSizeForComputedFileDigests);
lastKnownCacheSize = options.cacheSizeForComputedFileDigests;
}
if (options.cacheSizeForComputedFileDigests == 0) {
stats = null;
logger.atInfo().log("Disabled cache");
} else {
stats = DigestUtils.getCacheStats();
logStats("Accumulated cache stats before command", stats);
}
}
@Override
public void commandComplete() {
if (stats != null) {
CacheStats newStats = DigestUtils.getCacheStats();
Preconditions.checkNotNull(newStats, "The cache is enabled so we must get some stats back");
logStats("Accumulated cache stats after command", newStats);
logStats("Cache stats for finished command", newStats.minus(stats));
stats = null; // Silence stats until next command that uses the executor.
}
}
}