DfsBlockCacheConfig.java
/*
* Copyright (C) 2011, Google Inc. and others
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Distribution License v. 1.0 which is available at
* https://www.eclipse.org/org/documents/edl-v10.php.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
package org.eclipse.jgit.internal.storage.dfs;
import static org.eclipse.jgit.lib.ConfigConstants.CONFIG_CORE_SECTION;
import static org.eclipse.jgit.lib.ConfigConstants.CONFIG_DFS_SECTION;
import static org.eclipse.jgit.lib.ConfigConstants.CONFIG_KEY_BLOCK_LIMIT;
import static org.eclipse.jgit.lib.ConfigConstants.CONFIG_KEY_BLOCK_SIZE;
import static org.eclipse.jgit.lib.ConfigConstants.CONFIG_KEY_CONCURRENCY_LEVEL;
import static org.eclipse.jgit.lib.ConfigConstants.CONFIG_KEY_STREAM_RATIO;
import java.text.MessageFormat;
import java.util.Collections;
import java.util.Map;
import java.util.function.Consumer;
import org.eclipse.jgit.internal.JGitText;
import org.eclipse.jgit.internal.storage.pack.PackExt;
import org.eclipse.jgit.lib.Config;
/**
* Configuration parameters for
* {@link org.eclipse.jgit.internal.storage.dfs.DfsBlockCache}.
*/
public class DfsBlockCacheConfig {
/** 1024 (number of bytes in one kibibyte/kilobyte) */
public static final int KB = 1024;
/** 1024 {@link #KB} (number of bytes in one mebibyte/megabyte) */
public static final int MB = 1024 * KB;
/** Default number of max cache hits. */
public static final int DEFAULT_CACHE_HOT_MAX = 1;
private long blockLimit;
private int blockSize;
private double streamRatio;
private int concurrencyLevel;
private Consumer<Long> refLock;
private Map<PackExt, Integer> cacheHotMap;
/**
* Create a default configuration.
*/
public DfsBlockCacheConfig() {
setBlockLimit(32 * MB);
setBlockSize(64 * KB);
setStreamRatio(0.30);
setConcurrencyLevel(32);
cacheHotMap = Collections.emptyMap();
}
/**
* Get maximum number bytes of heap memory to dedicate to caching pack file
* data.
*
* @return maximum number bytes of heap memory to dedicate to caching pack
* file data. <b>Default is 32 MB.</b>
*/
public long getBlockLimit() {
return blockLimit;
}
/**
* Set maximum number bytes of heap memory to dedicate to caching pack file
* data.
* <p>
* It is strongly recommended to set the block limit to be an integer multiple
* of the block size. This constraint is not enforced by this method (since
* it may be called before {@link #setBlockSize(int)}), but it is enforced by
* {@link #fromConfig(Config)}.
*
* @param newLimit
* maximum number bytes of heap memory to dedicate to caching
* pack file data; must be positive.
* @return {@code this}
*/
public DfsBlockCacheConfig setBlockLimit(long newLimit) {
if (newLimit <= 0) {
throw new IllegalArgumentException(MessageFormat.format(
JGitText.get().blockLimitNotPositive,
Long.valueOf(newLimit)));
}
blockLimit = newLimit;
return this;
}
/**
* Get size in bytes of a single window mapped or read in from the pack
* file.
*
* @return size in bytes of a single window mapped or read in from the pack
* file. <b>Default is 64 KB.</b>
*/
public int getBlockSize() {
return blockSize;
}
/**
* Set size in bytes of a single window read in from the pack file.
*
* @param newSize
* size in bytes of a single window read in from the pack file.
* The value must be a power of 2.
* @return {@code this}
*/
public DfsBlockCacheConfig setBlockSize(int newSize) {
int size = Math.max(512, newSize);
if ((size & (size - 1)) != 0) {
throw new IllegalArgumentException(
JGitText.get().blockSizeNotPowerOf2);
}
blockSize = size;
return this;
}
/**
* Get the estimated number of threads concurrently accessing the cache.
*
* @return the estimated number of threads concurrently accessing the cache.
* <b>Default is 32.</b>
*/
public int getConcurrencyLevel() {
return concurrencyLevel;
}
/**
* Set the estimated number of threads concurrently accessing the cache.
*
* @param newConcurrencyLevel
* the estimated number of threads concurrently accessing the
* cache.
* @return {@code this}
*/
public DfsBlockCacheConfig setConcurrencyLevel(
final int newConcurrencyLevel) {
concurrencyLevel = newConcurrencyLevel;
return this;
}
/**
* Get highest percentage of {@link #getBlockLimit()} a single pack can
* occupy while being copied by the pack reuse strategy.
*
* @return highest percentage of {@link #getBlockLimit()} a single pack can
* occupy while being copied by the pack reuse strategy. <b>Default
* is 0.30, or 30%</b>.
*/
public double getStreamRatio() {
return streamRatio;
}
/**
* Set percentage of cache to occupy with a copied pack.
*
* @param ratio
* percentage of cache to occupy with a copied pack.
* @return {@code this}
*/
public DfsBlockCacheConfig setStreamRatio(double ratio) {
streamRatio = Math.max(0, Math.min(ratio, 1.0));
return this;
}
/**
* Get the consumer of the object reference lock wait time in milliseconds.
*
* @return consumer of wait time in milliseconds.
*/
public Consumer<Long> getRefLockWaitTimeConsumer() {
return refLock;
}
/**
* Set the consumer for lock wait time.
*
* @param c
* consumer of wait time in milliseconds.
* @return {@code this}
*/
public DfsBlockCacheConfig setRefLockWaitTimeConsumer(Consumer<Long> c) {
refLock = c;
return this;
}
/**
* Get the map of hot count per pack extension for {@code DfsBlockCache}.
*
* @return map of hot count per pack extension for {@code DfsBlockCache}.
*/
public Map<PackExt, Integer> getCacheHotMap() {
return cacheHotMap;
}
/**
* Set the map of hot count per pack extension for {@code DfsBlockCache}.
*
* @param cacheHotMap
* map of hot count per pack extension for {@code DfsBlockCache}.
* @return {@code this}
*/
public DfsBlockCacheConfig setCacheHotMap(
Map<PackExt, Integer> cacheHotMap) {
this.cacheHotMap = Collections.unmodifiableMap(cacheHotMap);
return this;
}
/**
* Update properties by setting fields from the configuration.
* <p>
* If a property is not defined in the configuration, then it is left
* unmodified.
* <p>
* Enforces certain constraints on the combination of settings in the config,
* for example that the block limit is a multiple of the block size.
*
* @param rc
* configuration to read properties from.
* @return {@code this}
*/
public DfsBlockCacheConfig fromConfig(Config rc) {
long cfgBlockLimit = rc.getLong(
CONFIG_CORE_SECTION,
CONFIG_DFS_SECTION,
CONFIG_KEY_BLOCK_LIMIT,
getBlockLimit());
int cfgBlockSize = rc.getInt(
CONFIG_CORE_SECTION,
CONFIG_DFS_SECTION,
CONFIG_KEY_BLOCK_SIZE,
getBlockSize());
if (cfgBlockLimit % cfgBlockSize != 0) {
throw new IllegalArgumentException(MessageFormat.format(
JGitText.get().blockLimitNotMultipleOfBlockSize,
Long.valueOf(cfgBlockLimit),
Long.valueOf(cfgBlockSize)));
}
setBlockLimit(cfgBlockLimit);
setBlockSize(cfgBlockSize);
setConcurrencyLevel(rc.getInt(
CONFIG_CORE_SECTION,
CONFIG_DFS_SECTION,
CONFIG_KEY_CONCURRENCY_LEVEL,
getConcurrencyLevel()));
String v = rc.getString(
CONFIG_CORE_SECTION,
CONFIG_DFS_SECTION,
CONFIG_KEY_STREAM_RATIO);
if (v != null) {
try {
setStreamRatio(Double.parseDouble(v));
} catch (NumberFormatException e) {
throw new IllegalArgumentException(MessageFormat.format(
JGitText.get().enumValueNotSupported3,
CONFIG_CORE_SECTION,
CONFIG_DFS_SECTION,
CONFIG_KEY_STREAM_RATIO, v), e);
}
}
return this;
}
}