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Pulls down netty.io, relocates nd then makes a fat new jar with them all in it.
The newest version!
/*
* Copyright 2012 The Netty Project
*
* The Netty Project licenses this file to you 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 ch.cern.hbase.thirdparty.io.netty.buffer;
import static ch.cern.hbase.thirdparty.io.netty.util.internal.ObjectUtil.checkPositiveOrZero;
import ch.cern.hbase.thirdparty.io.netty.util.NettyRuntime;
import ch.cern.hbase.thirdparty.io.netty.util.concurrent.FastThreadLocal;
import ch.cern.hbase.thirdparty.io.netty.util.concurrent.FastThreadLocalThread;
import ch.cern.hbase.thirdparty.io.netty.util.internal.PlatformDependent;
import ch.cern.hbase.thirdparty.io.netty.util.internal.StringUtil;
import ch.cern.hbase.thirdparty.io.netty.util.internal.SystemPropertyUtil;
import ch.cern.hbase.thirdparty.io.netty.util.internal.logging.InternalLogger;
import ch.cern.hbase.thirdparty.io.netty.util.internal.logging.InternalLoggerFactory;
import java.nio.ByteBuffer;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
public class PooledByteBufAllocator extends AbstractByteBufAllocator implements ByteBufAllocatorMetricProvider {
private static final InternalLogger logger = InternalLoggerFactory.getInstance(PooledByteBufAllocator.class);
private static final int DEFAULT_NUM_HEAP_ARENA;
private static final int DEFAULT_NUM_DIRECT_ARENA;
private static final int DEFAULT_PAGE_SIZE;
private static final int DEFAULT_MAX_ORDER; // 8192 << 11 = 16 MiB per chunk
private static final int DEFAULT_TINY_CACHE_SIZE;
private static final int DEFAULT_SMALL_CACHE_SIZE;
private static final int DEFAULT_NORMAL_CACHE_SIZE;
private static final int DEFAULT_MAX_CACHED_BUFFER_CAPACITY;
private static final int DEFAULT_CACHE_TRIM_INTERVAL;
private static final boolean DEFAULT_USE_CACHE_FOR_ALL_THREADS;
private static final int DEFAULT_DIRECT_MEMORY_CACHE_ALIGNMENT;
static final int DEFAULT_MAX_CACHED_BYTEBUFFERS_PER_CHUNK;
private static final int MIN_PAGE_SIZE = 4096;
private static final int MAX_CHUNK_SIZE = (int) (((long) Integer.MAX_VALUE + 1) / 2);
static {
int defaultPageSize = SystemPropertyUtil.getInt("ch.cern.hbase.thirdparty.io.netty.allocator.pageSize", 8192);
Throwable pageSizeFallbackCause = null;
try {
validateAndCalculatePageShifts(defaultPageSize);
} catch (Throwable t) {
pageSizeFallbackCause = t;
defaultPageSize = 8192;
}
DEFAULT_PAGE_SIZE = defaultPageSize;
int defaultMaxOrder = SystemPropertyUtil.getInt("ch.cern.hbase.thirdparty.io.netty.allocator.maxOrder", 11);
Throwable maxOrderFallbackCause = null;
try {
validateAndCalculateChunkSize(DEFAULT_PAGE_SIZE, defaultMaxOrder);
} catch (Throwable t) {
maxOrderFallbackCause = t;
defaultMaxOrder = 11;
}
DEFAULT_MAX_ORDER = defaultMaxOrder;
// Determine reasonable default for nHeapArena and nDirectArena.
// Assuming each arena has 3 chunks, the pool should not consume more than 50% of max memory.
final Runtime runtime = Runtime.getRuntime();
/*
* We use 2 * available processors by default to reduce contention as we use 2 * available processors for the
* number of EventLoops in NIO and EPOLL as well. If we choose a smaller number we will run into hot spots as
* allocation and de-allocation needs to be synchronized on the PoolArena.
*
* See https://github.com/netty/netty/issues/3888.
*/
final int defaultMinNumArena = NettyRuntime.availableProcessors() * 2;
final int defaultChunkSize = DEFAULT_PAGE_SIZE << DEFAULT_MAX_ORDER;
DEFAULT_NUM_HEAP_ARENA = Math.max(0,
SystemPropertyUtil.getInt(
"ch.cern.hbase.thirdparty.io.netty.allocator.numHeapArenas",
(int) Math.min(
defaultMinNumArena,
runtime.maxMemory() / defaultChunkSize / 2 / 3)));
DEFAULT_NUM_DIRECT_ARENA = Math.max(0,
SystemPropertyUtil.getInt(
"ch.cern.hbase.thirdparty.io.netty.allocator.numDirectArenas",
(int) Math.min(
defaultMinNumArena,
PlatformDependent.maxDirectMemory() / defaultChunkSize / 2 / 3)));
// cache sizes
DEFAULT_TINY_CACHE_SIZE = SystemPropertyUtil.getInt("ch.cern.hbase.thirdparty.io.netty.allocator.tinyCacheSize", 512);
DEFAULT_SMALL_CACHE_SIZE = SystemPropertyUtil.getInt("ch.cern.hbase.thirdparty.io.netty.allocator.smallCacheSize", 256);
DEFAULT_NORMAL_CACHE_SIZE = SystemPropertyUtil.getInt("ch.cern.hbase.thirdparty.io.netty.allocator.normalCacheSize", 64);
// 32 kb is the default maximum capacity of the cached buffer. Similar to what is explained in
// 'Scalable memory allocation using jemalloc'
DEFAULT_MAX_CACHED_BUFFER_CAPACITY = SystemPropertyUtil.getInt(
"ch.cern.hbase.thirdparty.io.netty.allocator.maxCachedBufferCapacity", 32 * 1024);
// the number of threshold of allocations when cached entries will be freed up if not frequently used
DEFAULT_CACHE_TRIM_INTERVAL = SystemPropertyUtil.getInt(
"ch.cern.hbase.thirdparty.io.netty.allocator.cacheTrimInterval", 8192);
DEFAULT_USE_CACHE_FOR_ALL_THREADS = SystemPropertyUtil.getBoolean(
"ch.cern.hbase.thirdparty.io.netty.allocator.useCacheForAllThreads", true);
DEFAULT_DIRECT_MEMORY_CACHE_ALIGNMENT = SystemPropertyUtil.getInt(
"ch.cern.hbase.thirdparty.io.netty.allocator.directMemoryCacheAlignment", 0);
// Use 1023 by default as we use an ArrayDeque as backing storage which will then allocate an internal array
// of 1024 elements. Otherwise we would allocate 2048 and only use 1024 which is wasteful.
DEFAULT_MAX_CACHED_BYTEBUFFERS_PER_CHUNK = SystemPropertyUtil.getInt(
"ch.cern.hbase.thirdparty.io.netty.allocator.maxCachedByteBuffersPerChunk", 1023);
if (logger.isDebugEnabled()) {
logger.debug("-Dio.netty.allocator.numHeapArenas: {}", DEFAULT_NUM_HEAP_ARENA);
logger.debug("-Dio.netty.allocator.numDirectArenas: {}", DEFAULT_NUM_DIRECT_ARENA);
if (pageSizeFallbackCause == null) {
logger.debug("-Dio.netty.allocator.pageSize: {}", DEFAULT_PAGE_SIZE);
} else {
logger.debug("-Dio.netty.allocator.pageSize: {}", DEFAULT_PAGE_SIZE, pageSizeFallbackCause);
}
if (maxOrderFallbackCause == null) {
logger.debug("-Dio.netty.allocator.maxOrder: {}", DEFAULT_MAX_ORDER);
} else {
logger.debug("-Dio.netty.allocator.maxOrder: {}", DEFAULT_MAX_ORDER, maxOrderFallbackCause);
}
logger.debug("-Dio.netty.allocator.chunkSize: {}", DEFAULT_PAGE_SIZE << DEFAULT_MAX_ORDER);
logger.debug("-Dio.netty.allocator.tinyCacheSize: {}", DEFAULT_TINY_CACHE_SIZE);
logger.debug("-Dio.netty.allocator.smallCacheSize: {}", DEFAULT_SMALL_CACHE_SIZE);
logger.debug("-Dio.netty.allocator.normalCacheSize: {}", DEFAULT_NORMAL_CACHE_SIZE);
logger.debug("-Dio.netty.allocator.maxCachedBufferCapacity: {}", DEFAULT_MAX_CACHED_BUFFER_CAPACITY);
logger.debug("-Dio.netty.allocator.cacheTrimInterval: {}", DEFAULT_CACHE_TRIM_INTERVAL);
logger.debug("-Dio.netty.allocator.useCacheForAllThreads: {}", DEFAULT_USE_CACHE_FOR_ALL_THREADS);
logger.debug("-Dio.netty.allocator.maxCachedByteBuffersPerChunk: {}",
DEFAULT_MAX_CACHED_BYTEBUFFERS_PER_CHUNK);
}
}
public static final PooledByteBufAllocator DEFAULT =
new PooledByteBufAllocator(PlatformDependent.directBufferPreferred());
private final PoolArena[] heapArenas;
private final PoolArena[] directArenas;
private final int tinyCacheSize;
private final int smallCacheSize;
private final int normalCacheSize;
private final List heapArenaMetrics;
private final List directArenaMetrics;
private final PoolThreadLocalCache threadCache;
private final int chunkSize;
private final PooledByteBufAllocatorMetric metric;
public PooledByteBufAllocator() {
this(false);
}
@SuppressWarnings("deprecation")
public PooledByteBufAllocator(boolean preferDirect) {
this(preferDirect, DEFAULT_NUM_HEAP_ARENA, DEFAULT_NUM_DIRECT_ARENA, DEFAULT_PAGE_SIZE, DEFAULT_MAX_ORDER);
}
@SuppressWarnings("deprecation")
public PooledByteBufAllocator(int nHeapArena, int nDirectArena, int pageSize, int maxOrder) {
this(false, nHeapArena, nDirectArena, pageSize, maxOrder);
}
/**
* @deprecated use
* {@link PooledByteBufAllocator#PooledByteBufAllocator(boolean, int, int, int, int, int, int, int, boolean)}
*/
@Deprecated
public PooledByteBufAllocator(boolean preferDirect, int nHeapArena, int nDirectArena, int pageSize, int maxOrder) {
this(preferDirect, nHeapArena, nDirectArena, pageSize, maxOrder,
DEFAULT_TINY_CACHE_SIZE, DEFAULT_SMALL_CACHE_SIZE, DEFAULT_NORMAL_CACHE_SIZE);
}
/**
* @deprecated use
* {@link PooledByteBufAllocator#PooledByteBufAllocator(boolean, int, int, int, int, int, int, int, boolean)}
*/
@Deprecated
public PooledByteBufAllocator(boolean preferDirect, int nHeapArena, int nDirectArena, int pageSize, int maxOrder,
int tinyCacheSize, int smallCacheSize, int normalCacheSize) {
this(preferDirect, nHeapArena, nDirectArena, pageSize, maxOrder, tinyCacheSize, smallCacheSize,
normalCacheSize, DEFAULT_USE_CACHE_FOR_ALL_THREADS, DEFAULT_DIRECT_MEMORY_CACHE_ALIGNMENT);
}
public PooledByteBufAllocator(boolean preferDirect, int nHeapArena,
int nDirectArena, int pageSize, int maxOrder, int tinyCacheSize,
int smallCacheSize, int normalCacheSize,
boolean useCacheForAllThreads) {
this(preferDirect, nHeapArena, nDirectArena, pageSize, maxOrder,
tinyCacheSize, smallCacheSize, normalCacheSize,
useCacheForAllThreads, DEFAULT_DIRECT_MEMORY_CACHE_ALIGNMENT);
}
public PooledByteBufAllocator(boolean preferDirect, int nHeapArena, int nDirectArena, int pageSize, int maxOrder,
int tinyCacheSize, int smallCacheSize, int normalCacheSize,
boolean useCacheForAllThreads, int directMemoryCacheAlignment) {
super(preferDirect);
threadCache = new PoolThreadLocalCache(useCacheForAllThreads);
this.tinyCacheSize = tinyCacheSize;
this.smallCacheSize = smallCacheSize;
this.normalCacheSize = normalCacheSize;
chunkSize = validateAndCalculateChunkSize(pageSize, maxOrder);
checkPositiveOrZero(nHeapArena, "nHeapArena");
checkPositiveOrZero(nDirectArena, "nDirectArena");
checkPositiveOrZero(directMemoryCacheAlignment, "directMemoryCacheAlignment");
if (directMemoryCacheAlignment > 0 && !isDirectMemoryCacheAlignmentSupported()) {
throw new IllegalArgumentException("directMemoryCacheAlignment is not supported");
}
if ((directMemoryCacheAlignment & -directMemoryCacheAlignment) != directMemoryCacheAlignment) {
throw new IllegalArgumentException("directMemoryCacheAlignment: "
+ directMemoryCacheAlignment + " (expected: power of two)");
}
int pageShifts = validateAndCalculatePageShifts(pageSize);
if (nHeapArena > 0) {
heapArenas = newArenaArray(nHeapArena);
List metrics = new ArrayList(heapArenas.length);
for (int i = 0; i < heapArenas.length; i ++) {
PoolArena.HeapArena arena = new PoolArena.HeapArena(this,
pageSize, maxOrder, pageShifts, chunkSize,
directMemoryCacheAlignment);
heapArenas[i] = arena;
metrics.add(arena);
}
heapArenaMetrics = Collections.unmodifiableList(metrics);
} else {
heapArenas = null;
heapArenaMetrics = Collections.emptyList();
}
if (nDirectArena > 0) {
directArenas = newArenaArray(nDirectArena);
List metrics = new ArrayList(directArenas.length);
for (int i = 0; i < directArenas.length; i ++) {
PoolArena.DirectArena arena = new PoolArena.DirectArena(
this, pageSize, maxOrder, pageShifts, chunkSize, directMemoryCacheAlignment);
directArenas[i] = arena;
metrics.add(arena);
}
directArenaMetrics = Collections.unmodifiableList(metrics);
} else {
directArenas = null;
directArenaMetrics = Collections.emptyList();
}
metric = new PooledByteBufAllocatorMetric(this);
}
@SuppressWarnings("unchecked")
private static PoolArena[] newArenaArray(int size) {
return new PoolArena[size];
}
private static int validateAndCalculatePageShifts(int pageSize) {
if (pageSize < MIN_PAGE_SIZE) {
throw new IllegalArgumentException("pageSize: " + pageSize + " (expected: " + MIN_PAGE_SIZE + ")");
}
if ((pageSize & pageSize - 1) != 0) {
throw new IllegalArgumentException("pageSize: " + pageSize + " (expected: power of 2)");
}
// Logarithm base 2. At this point we know that pageSize is a power of two.
return Integer.SIZE - 1 - Integer.numberOfLeadingZeros(pageSize);
}
private static int validateAndCalculateChunkSize(int pageSize, int maxOrder) {
if (maxOrder > 14) {
throw new IllegalArgumentException("maxOrder: " + maxOrder + " (expected: 0-14)");
}
// Ensure the resulting chunkSize does not overflow.
int chunkSize = pageSize;
for (int i = maxOrder; i > 0; i --) {
if (chunkSize > MAX_CHUNK_SIZE / 2) {
throw new IllegalArgumentException(String.format(
"pageSize (%d) << maxOrder (%d) must not exceed %d", pageSize, maxOrder, MAX_CHUNK_SIZE));
}
chunkSize <<= 1;
}
return chunkSize;
}
@Override
protected ByteBuf newHeapBuffer(int initialCapacity, int maxCapacity) {
PoolThreadCache cache = threadCache.get();
PoolArena heapArena = cache.heapArena;
final ByteBuf buf;
if (heapArena != null) {
buf = heapArena.allocate(cache, initialCapacity, maxCapacity);
} else {
buf = PlatformDependent.hasUnsafe() ?
new UnpooledUnsafeHeapByteBuf(this, initialCapacity, maxCapacity) :
new UnpooledHeapByteBuf(this, initialCapacity, maxCapacity);
}
return toLeakAwareBuffer(buf);
}
@Override
protected ByteBuf newDirectBuffer(int initialCapacity, int maxCapacity) {
PoolThreadCache cache = threadCache.get();
PoolArena directArena = cache.directArena;
final ByteBuf buf;
if (directArena != null) {
buf = directArena.allocate(cache, initialCapacity, maxCapacity);
} else {
buf = PlatformDependent.hasUnsafe() ?
UnsafeByteBufUtil.newUnsafeDirectByteBuf(this, initialCapacity, maxCapacity) :
new UnpooledDirectByteBuf(this, initialCapacity, maxCapacity);
}
return toLeakAwareBuffer(buf);
}
/**
* Default number of heap arenas - System Property: ch.cern.hbase.thirdparty.io.netty.allocator.numHeapArenas - default 2 * cores
*/
public static int defaultNumHeapArena() {
return DEFAULT_NUM_HEAP_ARENA;
}
/**
* Default number of direct arenas - System Property: ch.cern.hbase.thirdparty.io.netty.allocator.numDirectArenas - default 2 * cores
*/
public static int defaultNumDirectArena() {
return DEFAULT_NUM_DIRECT_ARENA;
}
/**
* Default buffer page size - System Property: ch.cern.hbase.thirdparty.io.netty.allocator.pageSize - default 8192
*/
public static int defaultPageSize() {
return DEFAULT_PAGE_SIZE;
}
/**
* Default maximum order - System Property: ch.cern.hbase.thirdparty.io.netty.allocator.maxOrder - default 11
*/
public static int defaultMaxOrder() {
return DEFAULT_MAX_ORDER;
}
/**
* Default thread caching behavior - System Property: ch.cern.hbase.thirdparty.io.netty.allocator.useCacheForAllThreads - default true
*/
public static boolean defaultUseCacheForAllThreads() {
return DEFAULT_USE_CACHE_FOR_ALL_THREADS;
}
/**
* Default prefer direct - System Property: ch.cern.hbase.thirdparty.io.netty.noPreferDirect - default false
*/
public static boolean defaultPreferDirect() {
return PlatformDependent.directBufferPreferred();
}
/**
* Default tiny cache size - System Property: ch.cern.hbase.thirdparty.io.netty.allocator.tinyCacheSize - default 512
*/
public static int defaultTinyCacheSize() {
return DEFAULT_TINY_CACHE_SIZE;
}
/**
* Default small cache size - System Property: ch.cern.hbase.thirdparty.io.netty.allocator.smallCacheSize - default 256
*/
public static int defaultSmallCacheSize() {
return DEFAULT_SMALL_CACHE_SIZE;
}
/**
* Default normal cache size - System Property: ch.cern.hbase.thirdparty.io.netty.allocator.normalCacheSize - default 64
*/
public static int defaultNormalCacheSize() {
return DEFAULT_NORMAL_CACHE_SIZE;
}
/**
* Return {@code true} if direct memory cache alignment is supported, {@code false} otherwise.
*/
public static boolean isDirectMemoryCacheAlignmentSupported() {
return PlatformDependent.hasUnsafe();
}
@Override
public boolean isDirectBufferPooled() {
return directArenas != null;
}
/**
* Returns {@code true} if the calling {@link Thread} has a {@link ThreadLocal} cache for the allocated
* buffers.
*/
@Deprecated
public boolean hasThreadLocalCache() {
return threadCache.isSet();
}
/**
* Free all cached buffers for the calling {@link Thread}.
*/
@Deprecated
public void freeThreadLocalCache() {
threadCache.remove();
}
final class PoolThreadLocalCache extends FastThreadLocal {
private final boolean useCacheForAllThreads;
PoolThreadLocalCache(boolean useCacheForAllThreads) {
this.useCacheForAllThreads = useCacheForAllThreads;
}
@Override
protected synchronized PoolThreadCache initialValue() {
final PoolArena heapArena = leastUsedArena(heapArenas);
final PoolArena directArena = leastUsedArena(directArenas);
Thread current = Thread.currentThread();
if (useCacheForAllThreads || current instanceof FastThreadLocalThread) {
return new PoolThreadCache(
heapArena, directArena, tinyCacheSize, smallCacheSize, normalCacheSize,
DEFAULT_MAX_CACHED_BUFFER_CAPACITY, DEFAULT_CACHE_TRIM_INTERVAL);
}
// No caching so just use 0 as sizes.
return new PoolThreadCache(heapArena, directArena, 0, 0, 0, 0, 0);
}
@Override
protected void onRemoval(PoolThreadCache threadCache) {
threadCache.free();
}
private PoolArena leastUsedArena(PoolArena[] arenas) {
if (arenas == null || arenas.length == 0) {
return null;
}
PoolArena minArena = arenas[0];
for (int i = 1; i < arenas.length; i++) {
PoolArena arena = arenas[i];
if (arena.numThreadCaches.get() < minArena.numThreadCaches.get()) {
minArena = arena;
}
}
return minArena;
}
}
@Override
public PooledByteBufAllocatorMetric metric() {
return metric;
}
/**
* Return the number of heap arenas.
*
* @deprecated use {@link PooledByteBufAllocatorMetric#numHeapArenas()}.
*/
@Deprecated
public int numHeapArenas() {
return heapArenaMetrics.size();
}
/**
* Return the number of direct arenas.
*
* @deprecated use {@link PooledByteBufAllocatorMetric#numDirectArenas()}.
*/
@Deprecated
public int numDirectArenas() {
return directArenaMetrics.size();
}
/**
* Return a {@link List} of all heap {@link PoolArenaMetric}s that are provided by this pool.
*
* @deprecated use {@link PooledByteBufAllocatorMetric#heapArenas()}.
*/
@Deprecated
public List heapArenas() {
return heapArenaMetrics;
}
/**
* Return a {@link List} of all direct {@link PoolArenaMetric}s that are provided by this pool.
*
* @deprecated use {@link PooledByteBufAllocatorMetric#directArenas()}.
*/
@Deprecated
public List directArenas() {
return directArenaMetrics;
}
/**
* Return the number of thread local caches used by this {@link PooledByteBufAllocator}.
*
* @deprecated use {@link PooledByteBufAllocatorMetric#numThreadLocalCaches()}.
*/
@Deprecated
public int numThreadLocalCaches() {
PoolArena[] arenas = heapArenas != null ? heapArenas : directArenas;
if (arenas == null) {
return 0;
}
int total = 0;
for (PoolArena arena : arenas) {
total += arena.numThreadCaches.get();
}
return total;
}
/**
* Return the size of the tiny cache.
*
* @deprecated use {@link PooledByteBufAllocatorMetric#tinyCacheSize()}.
*/
@Deprecated
public int tinyCacheSize() {
return tinyCacheSize;
}
/**
* Return the size of the small cache.
*
* @deprecated use {@link PooledByteBufAllocatorMetric#smallCacheSize()}.
*/
@Deprecated
public int smallCacheSize() {
return smallCacheSize;
}
/**
* Return the size of the normal cache.
*
* @deprecated use {@link PooledByteBufAllocatorMetric#normalCacheSize()}.
*/
@Deprecated
public int normalCacheSize() {
return normalCacheSize;
}
/**
* Return the chunk size for an arena.
*
* @deprecated use {@link PooledByteBufAllocatorMetric#chunkSize()}.
*/
@Deprecated
public final int chunkSize() {
return chunkSize;
}
final long usedHeapMemory() {
return usedMemory(heapArenas);
}
final long usedDirectMemory() {
return usedMemory(directArenas);
}
private static long usedMemory(PoolArena[] arenas) {
if (arenas == null) {
return -1;
}
long used = 0;
for (PoolArena arena : arenas) {
used += arena.numActiveBytes();
if (used < 0) {
return Long.MAX_VALUE;
}
}
return used;
}
final PoolThreadCache threadCache() {
PoolThreadCache cache = threadCache.get();
assert cache != null;
return cache;
}
/**
* Returns the status of the allocator (which contains all metrics) as string. Be aware this may be expensive
* and so should not called too frequently.
*/
public String dumpStats() {
int heapArenasLen = heapArenas == null ? 0 : heapArenas.length;
StringBuilder buf = new StringBuilder(512)
.append(heapArenasLen)
.append(" heap arena(s):")
.append(StringUtil.NEWLINE);
if (heapArenasLen > 0) {
for (PoolArena a: heapArenas) {
buf.append(a);
}
}
int directArenasLen = directArenas == null ? 0 : directArenas.length;
buf.append(directArenasLen)
.append(" direct arena(s):")
.append(StringUtil.NEWLINE);
if (directArenasLen > 0) {
for (PoolArena a: directArenas) {
buf.append(a);
}
}
return buf.toString();
}
}