001/* 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache license, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the license for the specific language governing permissions and 015 * limitations under the license. 016 */ 017package org.apache.logging.log4j.core.appender; 018 019import java.io.File; 020import java.io.IOException; 021import java.io.OutputStream; 022import java.io.RandomAccessFile; 023import java.io.Serializable; 024import java.lang.reflect.Method; 025import java.nio.ByteOrder; 026import java.nio.MappedByteBuffer; 027import java.nio.channels.FileChannel; 028import java.security.AccessController; 029import java.security.PrivilegedActionException; 030import java.security.PrivilegedExceptionAction; 031import java.util.HashMap; 032import java.util.Map; 033import java.util.Objects; 034 035import org.apache.logging.log4j.core.Layout; 036import org.apache.logging.log4j.core.util.Closer; 037import org.apache.logging.log4j.core.util.NullOutputStream; 038 039//Lines too long... 040//CHECKSTYLE:OFF 041/** 042 * Extends OutputStreamManager but instead of using a buffered output stream, this class maps a region of a file into 043 * memory and writes to this memory region. 044 * <p> 045 * 046 * @see <a href="http://www.codeproject.com/Tips/683614/Things-to-Know-about-Memory-Mapped-File-in-Java"> 047 * http://www.codeproject.com/Tips/683614/Things-to-Know-about-Memory-Mapped-File-in-Java</a> 048 * @see <a href="http://bugs.java.com/view_bug.do?bug_id=6893654">http://bugs.java.com/view_bug.do?bug_id=6893654</a> 049 * @see <a href="http://bugs.java.com/view_bug.do?bug_id=4724038">http://bugs.java.com/view_bug.do?bug_id=4724038</a> 050 * @see <a 051 * href="http://stackoverflow.com/questions/9261316/memory-mapped-mappedbytebuffer-or-direct-bytebuffer-for-db-implementation"> 052 * http://stackoverflow.com/questions/9261316/memory-mapped-mappedbytebuffer-or-direct-bytebuffer-for-db-implementation</a> 053 * 054 * @since 2.1 055 */ 056//CHECKSTYLE:ON 057public class MemoryMappedFileManager extends OutputStreamManager { 058 /** 059 * Default length of region to map. 060 */ 061 static final int DEFAULT_REGION_LENGTH = 32 * 1024 * 1024; 062 private static final int MAX_REMAP_COUNT = 10; 063 private static final MemoryMappedFileManagerFactory FACTORY = new MemoryMappedFileManagerFactory(); 064 private static final double NANOS_PER_MILLISEC = 1000.0 * 1000.0; 065 066 private final boolean isForce; 067 private final int regionLength; 068 private final String advertiseURI; 069 private final RandomAccessFile randomAccessFile; 070 private final ThreadLocal<Boolean> isEndOfBatch = new ThreadLocal<>(); 071 private MappedByteBuffer mappedBuffer; 072 private long mappingOffset; 073 074 protected MemoryMappedFileManager(final RandomAccessFile file, final String fileName, final OutputStream os, 075 final boolean force, final long position, final int regionLength, final String advertiseURI, 076 final Layout<? extends Serializable> layout, final boolean writeHeader) throws IOException { 077 super(os, fileName, layout, writeHeader); 078 this.isForce = force; 079 this.randomAccessFile = Objects.requireNonNull(file, "RandomAccessFile"); 080 this.regionLength = regionLength; 081 this.advertiseURI = advertiseURI; 082 this.isEndOfBatch.set(Boolean.FALSE); 083 this.mappedBuffer = mmap(randomAccessFile.getChannel(), getFileName(), position, regionLength); 084 this.mappingOffset = position; 085 } 086 087 /** 088 * Returns the MemoryMappedFileManager. 089 * 090 * @param fileName The name of the file to manage. 091 * @param append true if the file should be appended to, false if it should be overwritten. 092 * @param isForce true if the contents should be flushed to disk on every write 093 * @param regionLength The mapped region length. 094 * @param advertiseURI the URI to use when advertising the file 095 * @param layout The layout. 096 * @return A MemoryMappedFileManager for the File. 097 */ 098 public static MemoryMappedFileManager getFileManager(final String fileName, final boolean append, 099 final boolean isForce, final int regionLength, final String advertiseURI, 100 final Layout<? extends Serializable> layout) { 101 return (MemoryMappedFileManager) getManager(fileName, new FactoryData(append, isForce, regionLength, 102 advertiseURI, layout), FACTORY); 103 } 104 105 public Boolean isEndOfBatch() { 106 return isEndOfBatch.get(); 107 } 108 109 public void setEndOfBatch(final boolean endOfBatch) { 110 this.isEndOfBatch.set(Boolean.valueOf(endOfBatch)); 111 } 112 113 @Override 114 protected synchronized void write(final byte[] bytes, int offset, int length) { 115 super.write(bytes, offset, length); // writes to dummy output stream 116 117 while (length > mappedBuffer.remaining()) { 118 final int chunk = mappedBuffer.remaining(); 119 mappedBuffer.put(bytes, offset, chunk); 120 offset += chunk; 121 length -= chunk; 122 remap(); 123 } 124 mappedBuffer.put(bytes, offset, length); 125 126 // no need to call flush() if force is true, 127 // already done in AbstractOutputStreamAppender.append 128 } 129 130 private synchronized void remap() { 131 final long offset = this.mappingOffset + mappedBuffer.position(); 132 final int length = mappedBuffer.remaining() + regionLength; 133 try { 134 unsafeUnmap(mappedBuffer); 135 final long fileLength = randomAccessFile.length() + regionLength; 136 LOGGER.debug("{} {} extending {} by {} bytes to {}", getClass().getSimpleName(), getName(), getFileName(), 137 regionLength, fileLength); 138 139 final long startNanos = System.nanoTime(); 140 randomAccessFile.setLength(fileLength); 141 final float millis = (float) ((System.nanoTime() - startNanos) / NANOS_PER_MILLISEC); 142 LOGGER.debug("{} {} extended {} OK in {} millis", getClass().getSimpleName(), getName(), getFileName(), 143 millis); 144 145 mappedBuffer = mmap(randomAccessFile.getChannel(), getFileName(), offset, length); 146 mappingOffset = offset; 147 } catch (final Exception ex) { 148 logError("unable to remap", ex); 149 } 150 } 151 152 @Override 153 public synchronized void flush() { 154 mappedBuffer.force(); 155 } 156 157 @Override 158 public synchronized void close() { 159 final long position = mappedBuffer.position(); 160 final long length = mappingOffset + position; 161 try { 162 unsafeUnmap(mappedBuffer); 163 } catch (final Exception ex) { 164 logError("unable to unmap MappedBuffer", ex); 165 } 166 try { 167 LOGGER.debug("MMapAppender closing. Setting {} length to {} (offset {} + position {})", getFileName(), 168 length, mappingOffset, position); 169 randomAccessFile.setLength(length); 170 randomAccessFile.close(); 171 } catch (final IOException ex) { 172 logError("unable to close MemoryMappedFile", ex); 173 } 174 } 175 176 public static MappedByteBuffer mmap(final FileChannel fileChannel, final String fileName, final long start, 177 final int size) throws IOException { 178 for (int i = 1;; i++) { 179 try { 180 LOGGER.debug("MMapAppender remapping {} start={}, size={}", fileName, start, size); 181 182 final long startNanos = System.nanoTime(); 183 final MappedByteBuffer map = fileChannel.map(FileChannel.MapMode.READ_WRITE, start, size); 184 map.order(ByteOrder.nativeOrder()); 185 186 final float millis = (float) ((System.nanoTime() - startNanos) / NANOS_PER_MILLISEC); 187 LOGGER.debug("MMapAppender remapped {} OK in {} millis", fileName, millis); 188 189 return map; 190 } catch (final IOException e) { 191 if (e.getMessage() == null || !e.getMessage().endsWith("user-mapped section open")) { 192 throw e; 193 } 194 LOGGER.debug("Remap attempt {}/{} failed. Retrying...", i, MAX_REMAP_COUNT, e); 195 if (i < MAX_REMAP_COUNT) { 196 Thread.yield(); 197 } else { 198 try { 199 Thread.sleep(1); 200 } catch (final InterruptedException ignored) { 201 Thread.currentThread().interrupt(); 202 throw e; 203 } 204 } 205 } 206 } 207 } 208 209 private static void unsafeUnmap(final MappedByteBuffer mbb) throws PrivilegedActionException { 210 LOGGER.debug("MMapAppender unmapping old buffer..."); 211 final long startNanos = System.nanoTime(); 212 AccessController.doPrivileged(new PrivilegedExceptionAction<Object>() { 213 @Override 214 public Object run() throws Exception { 215 final Method getCleanerMethod = mbb.getClass().getMethod("cleaner"); 216 getCleanerMethod.setAccessible(true); 217 final Object cleaner = getCleanerMethod.invoke(mbb); // sun.misc.Cleaner instance 218 final Method cleanMethod = cleaner.getClass().getMethod("clean"); 219 cleanMethod.invoke(cleaner); 220 return null; 221 } 222 }); 223 final float millis = (float) ((System.nanoTime() - startNanos) / NANOS_PER_MILLISEC); 224 LOGGER.debug("MMapAppender unmapped buffer OK in {} millis", millis); 225 } 226 227 /** 228 * Returns the name of the File being managed. 229 * 230 * @return The name of the File being managed. 231 */ 232 public String getFileName() { 233 return getName(); 234 } 235 236 /** 237 * Returns the length of the memory mapped region. 238 * 239 * @return the length of the mapped region 240 */ 241 public int getRegionLength() { 242 return regionLength; 243 } 244 245 /** 246 * Returns {@code true} if the content of the buffer should be forced to the storage device on every write, 247 * {@code false} otherwise. 248 * 249 * @return whether each write should be force-sync'ed 250 */ 251 public boolean isImmediateFlush() { 252 return isForce; 253 } 254 255 /** 256 * Gets this FileManager's content format specified by: 257 * <p> 258 * Key: "fileURI" Value: provided "advertiseURI" param. 259 * </p> 260 * 261 * @return Map of content format keys supporting FileManager 262 */ 263 @Override 264 public Map<String, String> getContentFormat() { 265 final Map<String, String> result = new HashMap<>(super.getContentFormat()); 266 result.put("fileURI", advertiseURI); 267 return result; 268 } 269 270 /** 271 * Factory Data. 272 */ 273 private static class FactoryData { 274 private final boolean append; 275 private final boolean force; 276 private final int regionLength; 277 private final String advertiseURI; 278 private final Layout<? extends Serializable> layout; 279 280 /** 281 * Constructor. 282 * 283 * @param append Append to existing file or truncate. 284 * @param force forces the memory content to be written to the storage device on every event 285 * @param regionLength length of the mapped region 286 */ 287 public FactoryData(final boolean append, final boolean force, final int regionLength, 288 final String advertiseURI, final Layout<? extends Serializable> layout) { 289 this.append = append; 290 this.force = force; 291 this.regionLength = regionLength; 292 this.advertiseURI = advertiseURI; 293 this.layout = layout; 294 } 295 } 296 297 /** 298 * Factory to create a MemoryMappedFileManager. 299 */ 300 private static class MemoryMappedFileManagerFactory 301 implements ManagerFactory<MemoryMappedFileManager, FactoryData> { 302 303 /** 304 * Create a MemoryMappedFileManager. 305 * 306 * @param name The name of the File. 307 * @param data The FactoryData 308 * @return The MemoryMappedFileManager for the File. 309 */ 310 @SuppressWarnings("resource") 311 @Override 312 public MemoryMappedFileManager createManager(final String name, final FactoryData data) { 313 final File file = new File(name); 314 final File parent = file.getParentFile(); 315 if (null != parent && !parent.exists()) { 316 parent.mkdirs(); 317 } 318 if (!data.append) { 319 file.delete(); 320 } 321 322 final boolean writeHeader = !data.append || !file.exists(); 323 final OutputStream os = NullOutputStream.NULL_OUTPUT_STREAM; 324 RandomAccessFile raf = null; 325 try { 326 raf = new RandomAccessFile(name, "rw"); 327 final long position = (data.append) ? raf.length() : 0; 328 raf.setLength(position + data.regionLength); 329 return new MemoryMappedFileManager(raf, name, os, data.force, position, data.regionLength, 330 data.advertiseURI, data.layout, writeHeader); 331 } catch (final Exception ex) { 332 LOGGER.error("MemoryMappedFileManager (" + name + ") " + ex, ex); 333 Closer.closeSilently(raf); 334 } 335 return null; 336 } 337 } 338}