/*
* Created on 03-Aug-2004
* Created by Paul Gardner
* Copyright (C) 2004, 2005, 2006 Aelitis, All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* AELITIS, SAS au capital de 46,603.30 euros
* 8 Allee Lenotre, La Grille Royale, 78600 Le Mesnil le Roi, France.
*
*/
package com.aelitis.azureus.core.diskmanager.cache.impl;
/**
* @author parg
*
*/
import java.io.File;
import java.util.*;
import org.gudy.azureus2.core3.torrent.*;
import org.gudy.azureus2.core3.util.*;
import org.gudy.azureus2.core3.config.*;
import org.gudy.azureus2.core3.logging.*;
import com.aelitis.azureus.core.diskmanager.cache.*;
import com.aelitis.azureus.core.diskmanager.file.*;
import com.aelitis.azureus.core.util.CaseSensitiveFileMap;
public class
CacheFileManagerImpl
implements CacheFileManager, AEDiagnosticsEvidenceGenerator
{
private static final LogIDs LOGID = LogIDs.CACHE;
public static final boolean DEBUG = false;
public static final int CACHE_CLEANER_TICKS = 60; // every 60 seconds
public static final int STATS_UPDATE_FREQUENCY = 1*1000; // 1 sec
public static final long DIRTY_CACHE_WRITE_MAX_AGE = 120*1000; // 2 mins
static{
if ( DEBUG ){
System.out.println( "**** Cache consistency debugging on ****" );
}
}
protected boolean cache_enabled;
protected boolean cache_read_enabled;
protected boolean cache_write_enabled;
protected long cache_size;
protected long cache_files_not_smaller_than;
protected long cache_minimum_free_size;
protected long cache_space_free;
private long cache_file_id_next = 0;
protected FMFileManager file_manager;
// copy on update semantics
protected WeakHashMap cache_files = new WeakHashMap();
protected WeakHashMap updated_cache_files = null;
// access order
protected LinkedHashMap cache_entries = new LinkedHashMap(1024, 0.75f, true );
protected CacheFileManagerStatsImpl stats;
// copy on update semantics
protected Map torrent_to_cache_file_map = new HashMap();
protected long cache_bytes_written;
protected long cache_bytes_read;
protected long file_bytes_written;
protected long file_bytes_read;
protected long cache_read_count;
protected long cache_write_count;
protected long file_read_count;
protected long file_write_count;
protected AEMonitor this_mon = new AEMonitor( "CacheFileManager" );
private long cleaner_ticks = CACHE_CLEANER_TICKS;
public
CacheFileManagerImpl()
{
AEDiagnostics.addEvidenceGenerator( this );
file_manager = FMFileManagerFactory.getSingleton();
boolean enabled = COConfigurationManager.getBooleanParameter( "diskmanager.perf.cache.enable" );
boolean enable_read = COConfigurationManager.getBooleanParameter( "diskmanager.perf.cache.enable.read" );
boolean enable_write = COConfigurationManager.getBooleanParameter( "diskmanager.perf.cache.enable.write" );
// units are MB
int size = 1024*1024*COConfigurationManager.getIntParameter( "diskmanager.perf.cache.size" );
// units are KB
int not_smaller_than = 1024*COConfigurationManager.getIntParameter( "notsmallerthan" );
if ( size <= 0 ){
Debug.out( "Invalid cache size parameter (" + size + "), caching disabled" );
enabled = false;
}
initialise( enabled, enable_read, enable_write, size, not_smaller_than );
}
protected void
initialise(
boolean enabled,
boolean enable_read,
boolean enable_write,
long size,
long not_smaller_than )
{
cache_enabled = enabled && ( enable_read || enable_write );
cache_read_enabled = enabled && enable_read;
cache_write_enabled = enabled && enable_write;
cache_size = size;
cache_files_not_smaller_than = not_smaller_than;
cache_minimum_free_size = cache_size/4;
cache_space_free = cache_size;
stats = new CacheFileManagerStatsImpl( this );
cacheStatsAndCleaner();
if (Logger.isEnabled())
Logger.log(new LogEvent(LOGID, "DiskCache: enabled = " + cache_enabled
+ ", read = " + cache_read_enabled + ", write = "
+ cache_write_enabled + ", size = " + cache_size + " B"));
}
protected boolean
isWriteCacheEnabled()
{
return( cache_write_enabled );
}
protected boolean
isReadCacheEnabled()
{
return( cache_read_enabled );
}
public CacheFile
createFile(
final CacheFileOwner owner,
File file,
int type )
throws CacheFileManagerException
{
final long my_id;
// we differentiate the
try{
this_mon.enter();
my_id = cache_file_id_next++;
}finally{
this_mon.exit();
}
try{
FMFile fm_file =
file_manager.createFile(
new FMFileOwner()
{
public String
getName()
{
return( owner.getCacheFileOwnerName() + "[" + my_id + "]" );
}
public TOTorrentFile
getTorrentFile()
{
return( owner.getCacheFileTorrentFile());
}
public File
getControlFile(
String name )
{
return( owner.getCacheFileControlFile( name ));
}
}, file,
type==CacheFile.CT_LINEAR?FMFile.FT_LINEAR:FMFile.FT_COMPACT );
TOTorrentFile tf = owner.getCacheFileTorrentFile();
CacheFile cf;
if (( tf != null && tf.getLength() < cache_files_not_smaller_than ) || !cache_enabled || owner.forceNoCache()){
cf = new CacheFileWithoutCache( this, fm_file, tf );
}else{
cf = new CacheFileWithCache( this, fm_file, tf );
try{
this_mon.enter();
if ( updated_cache_files == null ){
updated_cache_files = new WeakHashMap( cache_files );
}
// copy on write so readers don't need to synchronize or copy
updated_cache_files.put( cf, null );
if ( tf != null ){
Map new_map = new HashMap( torrent_to_cache_file_map );
new_map.put( tf, cf );
torrent_to_cache_file_map = new_map;
}
}finally{
this_mon.exit();
}
}
return( cf );
}catch( FMFileManagerException e ){
rethrow( null, e );
return( null );
}
}
public CacheFileManagerStats
getStats()
{
return( stats );
}
protected boolean
isCacheEnabled()
{
return( cache_enabled );
}
/**
* allocates space but does NOT add it to the cache list due to synchronization issues. Basically
* the caller mustn't hold their monitor when calling allocate, as a flush may result in one or more
* other files being flushed which results in their monitor being taken, and we've got an A->B and
* B->A classic deadlock situation. However, we must keep the file's cache and our cache in step.
* It is not acceptable to have an entry inserted into our records but not in the file's as this
* then screws up the flush algorithm (which assumes that if it finds an entry in our list, a flush
* of that file is guaranteed to release space). Therefore we add the cache entry in addCacheSpace
* so that the caller can safely do this while synchronised firstly on its monitor and then we can
* sync on our. Hence we only ever get A->B monitor grabs which won't deadlock
* @param file
* @param buffer
* @param file_position
* @param length
* @return
* @throws CacheFileManagerException
*/
protected CacheEntry
allocateCacheSpace(
int entry_type,
CacheFileWithCache file,
DirectByteBuffer buffer,
long file_position,
int length )
throws CacheFileManagerException
{
boolean ok = false;
boolean log = false;
while( !ok ){
// musn't invoke synchronised CacheFile methods while holding manager lock as this
// can cause deadlocks (as CacheFile calls manager methods with locks)
CacheEntry oldest_entry = null;
try{
this_mon.enter();
if ( length < cache_space_free || cache_space_free == cache_size ){
ok = true;
}else{
oldest_entry = (CacheEntry)cache_entries.keySet().iterator().next();
}
}finally{
this_mon.exit();
}
if ( !ok ){
log = true;
long old_free = cache_space_free;
CacheFileWithCache oldest_file = oldest_entry.getFile();
try{
oldest_file.flushCache( oldest_entry.getFilePosition(), true, cache_minimum_free_size );
}catch( CacheFileManagerException e ){
// if the flush failed on a file other than this one then we don't report the error here,
// rather we tag the existing file as failed so that when it is next accessed the error
// will be reported
if ( oldest_file != file ){
oldest_file.setPendingException( e );
}else{
throw( e );
}
}
long flushed = cache_space_free - old_free;
if (Logger.isEnabled()) {
TOTorrentFile tf = file.getTorrentFile();
TOTorrent torrent = tf == null ? null : tf.getTorrent();
Logger.log(new LogEvent(torrent, LOGID,
"DiskCache: cache full, flushed " + flushed + " from "
+ oldest_file.getName()));
}
if ( flushed == 0 ){
try{
this_mon.enter();
if ( cache_entries.size() > 0 &&
(CacheEntry)cache_entries.keySet().iterator().next() == oldest_entry ){
// hmm, something wrong with cache as the flush should have got rid
// of at least the oldest entry
throw( new CacheFileManagerException( null, "Cache inconsistent: 0 flushed"));
}
}finally{
this_mon.exit();
}
}
}
}
CacheEntry entry = new CacheEntry( entry_type, file, buffer, file_position, length );
if (log && Logger.isEnabled()) {
TOTorrentFile tf = file.getTorrentFile();
TOTorrent torrent = tf == null ? null : tf.getTorrent();
Logger.log(new LogEvent(torrent, LOGID, "DiskCache: cr="
+ cache_bytes_read + ",cw=" + cache_bytes_written + ",fr="
+ file_bytes_read + ",fw=" + file_bytes_written));
}
return( entry );
}
protected void
cacheStatsAndCleaner()
{
SimpleTimer.addPeriodicEvent(
"CacehFile:stats",
STATS_UPDATE_FREQUENCY,
new TimerEventPerformer() {
public void perform( TimerEvent ev ) {
stats.update();
// System.out.println( "cache file count = " + cache_files.size());
Iterator cf_it = cache_files.keySet().iterator();
while(cf_it.hasNext()){
((CacheFileWithCache)cf_it.next()).updateStats();
}
if ( --cleaner_ticks == 0 ){
cleaner_ticks = CACHE_CLEANER_TICKS;
final Set dirty_files = new HashSet();
final long oldest =SystemTime.getCurrentTime() - DIRTY_CACHE_WRITE_MAX_AGE;
try{
this_mon.enter();
if ( updated_cache_files != null ){
cache_files = updated_cache_files;
updated_cache_files = null;
}
if ( cache_entries.size() > 0 ){
Iterator it = cache_entries.keySet().iterator();
while( it.hasNext()){
CacheEntry entry = (CacheEntry)it.next();
// System.out.println( "oldest entry = " + ( now - entry.getLastUsed()));
if ( entry.isDirty()){
dirty_files.add( entry.getFile());
}
}
}
// System.out.println( "cache file = " + cache_files.size() + ", torrent map = " + torrent_to_cache_file_map.size());
}finally{
this_mon.exit();
}
Iterator it = dirty_files.iterator();
while( it.hasNext()){
CacheFileWithCache file = (CacheFileWithCache)it.next();
try{
TOTorrentFile tf = file.getTorrentFile();
long min_flush_size = -1;
if ( tf != null ){
min_flush_size = tf.getTorrent().getPieceLength();
}
file.flushOldDirtyData( oldest, min_flush_size );
}catch( CacheFileManagerException e ){
file.setPendingException( e );
// if this fails then the error should reoccur on a "proper"
// flush later and be reported
Debug.printStackTrace( e );
}catch( Throwable e ){
Debug.printStackTrace( e );
}
}
}
}
}
);
}
// must be called when the cachefileimpl is synchronised to ensure that the file's
// cache view and our cache view are consistent
protected void
addCacheSpace(
CacheEntry new_entry )
throws CacheFileManagerException
{
try{
this_mon.enter();
cache_space_free -= new_entry.getLength();
// System.out.println( "Total cache space = " + cache_space_free );
cache_entries.put( new_entry, new_entry );
if ( DEBUG ){
CacheFileWithCache file = new_entry.getFile();
long total_cache_size = 0;
int my_count = 0;
Iterator it = cache_entries.keySet().iterator();
while( it.hasNext()){
CacheEntry entry = (CacheEntry)it.next();
total_cache_size += entry.getLength();
if ( entry.getFile() == file ){
my_count++;
}
}
if ( my_count != file.cache.size()){
Debug.out( "Cache inconsistency: my count = " + my_count + ", file = " + file.cache.size());
throw( new CacheFileManagerException( null, "Cache inconsistency: counts differ"));
}else{
//System.out.println( "Cache: file_count = " + my_count );
}
if ( total_cache_size != cache_size - cache_space_free ){
Debug.out( "Cache inconsistency: used_size = " + total_cache_size + ", free = " + cache_space_free + ", size = " + cache_size );
throw( new CacheFileManagerException( null, "Cache inconsistency: sizes differ"));
}else{
//System.out.println( "Cache: usage = " + total_cache_size );
}
}
}finally{
this_mon.exit();
}
}
protected void
cacheEntryUsed(
CacheEntry entry )
throws CacheFileManagerException
{
try{
this_mon.enter();
// note that the "get" operation update the MRU in cache_entries
if ( cache_entries.get( entry ) == null ){
Debug.out( "Cache inconsistency: entry missing on usage" );
throw( new CacheFileManagerException( null, "Cache inconsistency: entry missing on usage"));
}else{
entry.used();
}
}finally{
this_mon.exit();
}
}
protected void
releaseCacheSpace(
CacheEntry entry )
throws CacheFileManagerException
{
entry.getBuffer().returnToPool();
try{
this_mon.enter();
cache_space_free += entry.getLength();
if ( cache_entries.remove( entry ) == null ){
Debug.out( "Cache inconsistency: entry missing on removal" );
throw( new CacheFileManagerException( null, "Cache inconsistency: entry missing on removal"));
}
/*
if ( entry.getType() == CacheEntry.CT_READ_AHEAD ){
if ( entry.getUsageCount() < 2 ){
System.out.println( "ra: not used" );
}else{
System.out.println( "ra: used" );
}
}
*/
// System.out.println( "Total cache space = " + cache_space_free );
}finally{
this_mon.exit();
}
}
protected long
getCacheSize()
{
return( cache_size );
}
protected long
getCacheUsed()
{
long free = cache_space_free;
if ( free < 0 ){
free = 0;
}
return( cache_size - free );
}
protected void
cacheBytesWritten(
long num )
{
try{
this_mon.enter();
cache_bytes_written += num;
cache_write_count++;
}finally{
this_mon.exit();
}
}
protected void
cacheBytesRead(
int num )
{
try{
this_mon.enter();
cache_bytes_read += num;
cache_read_count++;
}finally{
this_mon.exit();
}
}
protected void
fileBytesWritten(
long num )
{
try{
this_mon.enter();
file_bytes_written += num;
file_write_count++;
}finally{
this_mon.exit();
}
}
protected void
fileBytesRead(
int num )
{
try{
this_mon.enter();
file_bytes_read += num;
file_read_count++;
}finally{
this_mon.exit();
}
}
protected long
getBytesWrittenToCache()
{
return( cache_bytes_written );
}
protected long
getBytesWrittenToFile()
{
return( file_bytes_written );
}
protected long
getBytesReadFromCache()
{
return( cache_bytes_read );
}
protected long
getBytesReadFromFile()
{
return( file_bytes_read );
}
public long
getCacheReadCount()
{
return( cache_read_count );
}
public long
getCacheWriteCount()
{
return( cache_write_count );
}
public long
getFileReadCount()
{
return( file_read_count );
}
public long
getFileWriteCount()
{
return( file_write_count );
}
protected void
closeFile(
CacheFileWithCache file )
{
TOTorrentFile tf = file.getTorrentFile();
if ( tf != null && torrent_to_cache_file_map.get( tf ) != null ){
try{
this_mon.enter();
Map new_map = new HashMap( torrent_to_cache_file_map );
new_map.remove( tf );
torrent_to_cache_file_map = new_map;
}finally{
this_mon.exit();
}
}
}
protected boolean[] getBytesInCache(TOTorrent torrent, long[] absoluteOffsets, long[] lengths)
{
//sanity checks
if(absoluteOffsets.length != lengths.length)
throw new IllegalArgumentException("Offsets/Lengths mismatch");
long prevEnding = 0;
for(int i = 0;i<lengths.length;i++)
{
if(absoluteOffsets[i]<prevEnding || lengths[i] <= 0 )
throw new IllegalArgumentException("Offsets/Lengths are not in ascending order");
prevEnding = absoluteOffsets[i]+lengths[i];
}
Map map = torrent_to_cache_file_map;
TOTorrentFile[] files = torrent.getFiles();
boolean[] results = new boolean[absoluteOffsets.length];
Arrays.fill(results, true); // assume everything to be cached, then check for the opposite
final long first = absoluteOffsets[0];
final long last = absoluteOffsets[absoluteOffsets.length-1]+lengths[lengths.length-1];
boolean foundFile = false;
long fileOffset = 0;
for (int i=0;i<files.length;i++){
TOTorrentFile tf = files[i];
CacheFileWithCache cache_file = (CacheFileWithCache)map.get( tf );
long length = tf.getLength();
if(fileOffset > last || fileOffset+length < first)
{
fileOffset += length;
continue; // no chunk falls within that file, skip it
}
foundFile = true;
if(cache_file != null)
cache_file.getBytesInCache(results,absoluteOffsets,lengths);
else // we have no cache file and thus no cache entries
for(int j=0;j<results.length;j++) // check if any chunks fall into this non-file
if((absoluteOffsets[j] < fileOffset+length && absoluteOffsets[j] > fileOffset) || (absoluteOffsets[j]+lengths[j] < fileOffset+length && absoluteOffsets[j]+lengths[j] > fileOffset))
results[j] = false; // no file -> no cache entry
fileOffset += length;
}
if(!foundFile)
Arrays.fill(results, false);
return results;
}
protected void
rethrow(
CacheFile file,
FMFileManagerException e )
throws CacheFileManagerException
{
Throwable cause = e.getCause();
if ( cause != null ){
throw( new CacheFileManagerException( file, e.getMessage(), cause ));
}
throw( new CacheFileManagerException( file, e.getMessage(), e ));
}
public void
generate(
IndentWriter writer )
{
writer.println( "Cache Manager" );
try{
writer.indent();
Iterator it;
// grab a copy to avoid potential deadlock as we never take the manager monitor
// and then the file's own monitor, always the other way around
try{
this_mon.enter();
it = new ArrayList( cache_entries.keySet()).iterator();
}finally{
this_mon.exit();
}
writer.println( "Entries = " + cache_entries.size());
Set files = new HashSet();
while( it.hasNext()){
CacheEntry entry = (CacheEntry)it.next();
CacheFileWithCache file = entry.getFile();
if( !files.contains( file )){
files.add( file );
TOTorrentFile torrentFile = file.getTorrentFile();
String fileLength = "";
try {
fileLength = "" + file.getLength();
} catch (Exception e) {
if (torrentFile != null)
fileLength = "" + torrentFile.getLength();
}
String hash = "<unknown>";
try{
if (torrentFile != null)
hash = ByteFormatter.encodeString( torrentFile.getTorrent().getHash());
}catch( Throwable e ){
}
String name = file.getName();
writer.println("File: " + Debug.secretFileName(name) + ", size "
+ fileLength + ", torrent " + hash + ", access = "
+ file.getAccessMode());
}
}
}finally{
writer.exdent();
}
}
public void
setFileLinks(
TOTorrent torrent,
CaseSensitiveFileMap links )
{
file_manager.setFileLinks( torrent, links );
}
}
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