yacy_search_server/source/net/yacy/peers/Transmission.java
Michael Peter Christen 788288eb9e added the generation of 50 (!!) new solr field in the core 'webgraph'.
The default schema uses only some of them and the resting search index
has now the following properties:
- webgraph size will have about 40 times as much entries as default
index
- the complete index size will increase and may be about the double size
of current amount
As testing showed, not much indexing performance is lost. The default
index will be smaller (moved fields out of it); thus searching
can be faster.
The new index will cause that some old parts in YaCy can be removed,
i.e. specialized webgraph data and the noload crawler. The new index
will make it possible to:
- search within link texts of linked but not indexed documents (about 20
times of document index in size!!)
- get a very detailed link graph
- enhance ranking using a complete link graph

To get the full access to the new index, the API to solr has now two
access points: one with attribute core=collection1 for the default
search index and core=webgraph to the new webgraph search index. This is
also avaiable for p2p operation but client access is not yet
implemented.
2013-02-22 15:45:15 +01:00

302 lines
13 KiB
Java

// Transmission.java
// (C) 2009 by Michael Peter Christen; mc@yacy.net, Frankfurt a. M., Germany
// first published 09.02.2009 on http://yacy.net
//
// $LastChangedDate$
// $LastChangedRevision$
// $LastChangedBy$
//
// LICENSE
//
// 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
package net.yacy.peers;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Random;
import net.yacy.cora.document.ASCII;
import net.yacy.cora.storage.HandleSet;
import net.yacy.cora.util.SpaceExceededException;
import net.yacy.kelondro.data.word.Word;
import net.yacy.kelondro.data.word.WordReference;
import net.yacy.kelondro.data.word.WordReferenceRow;
import net.yacy.kelondro.index.RowHandleSet;
import net.yacy.kelondro.logging.Log;
import net.yacy.kelondro.rwi.ReferenceContainer;
import net.yacy.kelondro.rwi.ReferenceContainerCache;
import net.yacy.kelondro.workflow.WorkflowJob;
import net.yacy.search.index.Segment;
public class Transmission {
// The number of RWIs we can be sure a remote peer will accept
// anything beyond that might get discarded without notice
public static final int maxRWIsCount = 1000; // since SVN 7993 hardcoded in htroot/yacy/transferRWI.java:161
protected Log log;
protected Segment segment;
protected SeedDB seeds;
protected boolean gzipBody4Transfer;
protected int timeout4Transfer;
public Transmission(
final Log log,
final Segment segment,
final SeedDB seeds,
final boolean gzipBody4Transfer,
final int timeout4Transfer) {
this.log = log;
this.segment = segment;
this.seeds = seeds;
this.gzipBody4Transfer = gzipBody4Transfer;
this.timeout4Transfer = timeout4Transfer;
}
public Chunk newChunk(final byte[] primaryTarget, final List<Seed> targets) {
return new Chunk(primaryTarget, targets);
}
public class Chunk extends WorkflowJob implements Iterable<ReferenceContainer<WordReference>> {
/**
* a dispatcher entry contains
* - the primary target, which is a word hash, as marker for the entry
* - a set of indexContainers in a cache,
* - the associated URLs in a set to have a cache for the transmission
* to multiple peers and to ensure that all entries in the indexContainers
* have a reference in the urls
* - a set of yacy seeds which will shrink as the containers are transmitted to them
* - a counter that gives the number of sucessful and unsuccessful transmissions so far
*/
private final byte[] primaryTarget;
private final ReferenceContainerCache<WordReference> containers;
private final HandleSet references;
private final HandleSet badReferences;
private final List<Seed> targets;
private int hit, miss;
/**
* generate a new dispatcher target. such a target is defined with a primary target and
* a set of target peers that shall receive the entries of the containers
* the payloadrow defines the structure of container entries
* @param primaryTarget
* @param targets
*/
public Chunk(final byte[] primaryTarget, final List<Seed> targets) {
super();
this.primaryTarget = primaryTarget;
this.containers = new ReferenceContainerCache<WordReference>(Segment.wordReferenceFactory, Segment.wordOrder, Word.commonHashLength);
this.references = new RowHandleSet(WordReferenceRow.urlEntryRow.primaryKeyLength, WordReferenceRow.urlEntryRow.objectOrder, 0);
this.badReferences = new RowHandleSet(WordReferenceRow.urlEntryRow.primaryKeyLength, WordReferenceRow.urlEntryRow.objectOrder, 0);
this.targets = targets;
this.hit = 0;
this.miss = 0;
}
/*
* return a new container with at most max elements and put the rest back to the index
* as this chunk might be transferred back to myself a random selection needs to be taken
* @param container
* @param max
* @throws RowSpaceExceededException
* @return
*/
private ReferenceContainer<WordReference> trimContainer(final ReferenceContainer<WordReference> container, final int max) throws SpaceExceededException {
final ReferenceContainer<WordReference> c = new ReferenceContainer<WordReference>(Segment.wordReferenceFactory, container.getTermHash(), max);
final int part = container.size() / max + 1;
final Random r = new Random();
WordReference w;
final List<byte[]> selected = new ArrayList<byte[]>();
final Iterator<WordReference> i = container.entries();
while ((i.hasNext()) && (c.size() < max)) {
w = i.next();
if (r.nextInt(part) == 0) {
c.add(w);
selected.add(w.urlhash());
}
}
// remove the selected entries from container
for (final byte[] b : selected) container.removeReference(b);
// put container back
try {
Transmission.this.segment.storeRWI(container);
} catch (final Exception e) {
Log.logException(e);
}
return c;
}
/**
* add a container to the Entry cache.
* all entries in the container are checked and only such are stored which have a reference entry
* @param container
* @throws SpaceExceededException
*/
public void add(final ReferenceContainer<WordReference> container) throws SpaceExceededException {
int remaining = maxRWIsCount;
for (final ReferenceContainer<WordReference> ic : this) remaining -= ic.size();
if (remaining <= 0) {
// No space left in this chunk
try {
Transmission.this.segment.storeRWI(container);
} catch (final Exception e) {
Log.logException(e);
}
return;
}
final ReferenceContainer<WordReference> c = (remaining >= container.size()) ? container : trimContainer(container, remaining);
// iterate through the entries in the container and check if the reference is in the repository
final Iterator<WordReference> i = c.entries();
final List<byte[]> notFoundx = new ArrayList<byte[]>();
while (i.hasNext()) {
final WordReference e = i.next();
if (this.references.has(e.urlhash())) continue;
if (this.badReferences.has(e.urlhash())) {
notFoundx.add(e.urlhash());
continue;
}
if (!Transmission.this.segment.fulltext().exists(ASCII.String(e.urlhash()))) {
notFoundx.add(e.urlhash());
this.badReferences.put(e.urlhash());
} else {
this.references.put(e.urlhash());
}
}
// now delete all references that were not found
for (final byte[] b : notFoundx) c.removeReference(b);
// finally add the remaining container to the cache
this.containers.add(c);
}
/**
* get all containers from the entry. This method may be used to flush remaining entries
* if they had been finished transmission without success (not enough peers arrived)
*/
@Override
public Iterator<ReferenceContainer<WordReference>> iterator() {
return this.containers.iterator();
}
public int containersSize() {
return this.containers.size();
}
public byte[] primaryTarget() {
return this.primaryTarget;
}
/**
* return the number of successful transmissions
* @return
*/
public int hit() {
return this.hit;
}
/**
* return the number of unsuccessful transmissions
* @return
*/
public int miss() {
return this.miss;
}
/**
* return the number of targets that are left in the target cache
* if this is empty, there may be no more use of this object and it should be flushed
* with the iterator method
* @return
*/
public int targets() {
return this.targets.size();
}
public boolean transmit() {
if (this.targets.isEmpty()) return false;
final Seed target = this.targets.remove(0);
// transferring selected words to remote peer
if (target == Transmission.this.seeds.mySeed() || target.hash.equals(Transmission.this.seeds.mySeed().hash)) {
// target is my own peer. This is easy. Just restore the indexContainer
restore();
this.hit++;
Transmission.this.log.logInfo("Transfer of chunk to myself-target");
return true;
}
Transmission.this.log.logInfo("starting new index transmission request to " + ASCII.String(this.primaryTarget));
final long start = System.currentTimeMillis();
final String error = Protocol.transferIndex(target, this.containers, this.references, Transmission.this.segment, Transmission.this.gzipBody4Transfer, Transmission.this.timeout4Transfer);
if (error == null) {
// words successfully transfered
final long transferTime = System.currentTimeMillis() - start;
final Iterator<ReferenceContainer<WordReference>> i = this.containers.iterator();
final ReferenceContainer<WordReference> firstContainer = (i == null) ? null : i.next();
Transmission.this.log.logInfo("Index transfer of " + this.containers.size() +
" words [" + ((firstContainer == null) ? null : ASCII.String(firstContainer.getTermHash())) + " .. " + ASCII.String(this.primaryTarget) + "]" +
" and " + this.references.size() + " URLs" +
" to peer " + target.getName() + ":" + target.hash +
" in " + (transferTime / 1000) +
" seconds successful (" + (1000 * this.containers.size() / (transferTime + 1)) +
" words/s)");
Transmission.this.seeds.mySeed().incSI(this.containers.size());
Transmission.this.seeds.mySeed().incSU(this.references.size());
// if the peer has set a pause time and we are in flush mode (index transfer)
// then we pause for a while now
Transmission.this.log.logInfo("Transfer finished of chunk to target " + target.hash + "/" + target.getName());
this.hit++;
return true;
}
this.miss++;
// write information that peer does not receive index transmissions
Transmission.this.log.logInfo("Transfer failed of chunk to target " + target.hash + "/" + target.getName() + ": " + error);
// get possibly newer target Info
final Seed newTarget = Transmission.this.seeds.get(target.hash);
if (newTarget != null) {
final String oldAddress = target.getPublicAddress();
if ((oldAddress != null) && (oldAddress.equals(newTarget.getPublicAddress()))) {
newTarget.setFlagAcceptRemoteIndex(false);
Transmission.this.seeds.update(newTarget.hash, newTarget);
} else {
// we tried an old Address. Don't change anything
}
} else {
// target not in DB anymore. ???
}
return false;
}
public boolean isFinished() {
//System.out.println("canFinish: hit = " + this.hit + ", redundancy = " + seeds.redundancy() + ", targets.size() = " + targets.size());
return this.hit >= Transmission.this.seeds.redundancy();
}
public boolean canFinish() {
//System.out.println("canFinish: hit = " + this.hit + ", redundancy = " + seeds.redundancy() + ", targets.size() = " + targets.size());
return this.targets.size() >= Transmission.this.seeds.redundancy() - this.hit;
}
public void restore() {
for (final ReferenceContainer<WordReference> ic : this) try {
Transmission.this.segment.storeRWI(ic);
} catch (final Exception e) {
Log.logException(e);
}
}
}
}