- better synchronization in SortStack

- better ThreadGroup organization
- less worker threads for media search (64 was too much...)


git-svn-id: https://svn.berlios.de/svnroot/repos/yacy/trunk@6497 6c8d7289-2bf4-0310-a012-ef5d649a1542

htroot/yacysearchitem.java

@@ -215,7 +215,7 @@ public class yacysearchitem {
         if (s.length() <= length) return s;
         final int p = s.lastIndexOf('.');
         if (p < 0) return s.substring(0, length - 3) + "...";
-        return s.substring(0, length - (s.length() - p) - 3) + "..." + s.substring(p);
+        return s.substring(0, length - (s.length() - p) - 3) + "..." + s.substring(p); // TODO check oob
     }
     
     private static String sizename(int size) {

source/de/anomic/search/DocumentIndex.java

@@ -57,6 +57,8 @@ public class DocumentIndex extends Segment {
     private BlockingQueue<File> queue;
     private Worker[] worker;
     private CallbackListener callback;
+
+    private static final ThreadGroup workerThreadGroup = new ThreadGroup("workerThreadGroup");
     
     public DocumentIndex(Log log, final File segmentPath, CallbackListener callback, int cachesize) throws IOException {
         super(log, segmentPath, cachesize, targetFileSize * 4 - 1, false, false);
@@ -65,7 +67,7 @@ public class DocumentIndex extends Segment {
         this.queue = new LinkedBlockingQueue<File>(cores * 300);
         this.worker = new Worker[cores];
         for (int i = 0; i < cores; i++) {
-            this.worker[i] = new Worker();
+            this.worker[i] = new Worker(i);
             this.worker[i].start();
         }
     }
@@ -75,6 +77,10 @@ public class DocumentIndex extends Segment {
     }
 	
     class Worker extends Thread {
+        public Worker(int count) {
+            super(workerThreadGroup, "query-" + count);
+        }
+        
         public void run() {
             File f;
             URIMetadataRow resultRow;

source/de/anomic/search/RankingProcess.java

@@ -245,6 +245,7 @@ public final class RankingProcess extends Thread {
 			
 		    // kick out entries that are too bad according to current findings
 		    r = Long.valueOf(order.cardinal(fEntry));
+		    assert maxentries != 0;
 		    if ((maxentries >= 0) && (stack.size() >= maxentries) && (stack.bottom(r.longValue()))) continue;
 		    
 		    // insert

source/de/anomic/search/ResultFetcher.java

@@ -97,7 +97,7 @@ public class ResultFetcher {
         
         // start worker threads to fetch urls and snippets
         this.workerThreads = null;
-        deployWorker(query.itemsPerPage, query.neededResults());
+        deployWorker(Math.min(10, query.itemsPerPage), query.neededResults());
         MemoryTracker.update("SEARCH", new ProfilingGraph.searchEvent(query.id(true), this.workerThreads.length + " online snippet fetch threads started", 0, 0), false);
         
     }
@@ -302,7 +302,7 @@ public class ResultFetcher {
             (this.rankedCache.size() > this.result.size())
            ) {
         	// start worker threads to fetch urls and snippets
-            deployWorker(query.itemsPerPage, query.neededResults());
+            deployWorker(Math.min(10, query.itemsPerPage), query.neededResults());
         }
 
         // finally wait until enough results are there produced from the

source/de/anomic/server/serverCore.java

@@ -443,7 +443,7 @@ public final class serverCore extends AbstractBusyThread implements BusyThread {
     
     public List<Session> getJobList() {
         final Thread[] threadList = new Thread[sessionThreadGroup.activeCount()];     
-        serverCore.sessionThreadGroup.enumerate(threadList);
+        serverCore.sessionThreadGroup.enumerate(threadList, false);
         ArrayList<Session> l = new ArrayList<Session>();
         for (Thread t: threadList) {
             if (t == null) continue;

source/de/anomic/yacy/yacySearch.java

@@ -45,6 +45,8 @@ import de.anomic.yacy.dht.PeerSelection;
 
 public class yacySearch extends Thread {
 
+    private static final ThreadGroup ysThreadGroup = new ThreadGroup("yacySearchThreadGroup");
+    
     final private String wordhashes, excludehashes, urlhashes, sitehash, authorhash;
     final private boolean global;
     final private int partitions;
@@ -79,7 +81,7 @@ public class yacySearch extends Thread {
               final Blacklist blacklist,
               final RankingProfile rankingProfile,
               final Bitfield constraint) {
-        super("yacySearch_" + targetPeer.getName());
+        super(ysThreadGroup, "yacySearch_" + targetPeer.getName());
         //System.out.println("DEBUG - yacySearch thread " + this.getName() + " initialized " + ((urlhashes.length() == 0) ? "(primary)" : "(secondary)"));
         assert wordhashes.length() >= 12;
         this.wordhashes = wordhashes;

source/net/yacy/kelondro/util/SortStack.java

@@ -26,28 +26,29 @@
 
 package net.yacy.kelondro.util;
 
-import java.util.HashSet;
 import java.util.Iterator;
 import java.util.LinkedList;
 import java.util.List;
 import java.util.Map;
 import java.util.TreeMap;
+import java.util.concurrent.ConcurrentHashMap;
 
 public class SortStack<E> {
 
     // implements a stack where elements 'float' on-top of the stack according to a weight value.
     // objects pushed on the stack must implement the hashCode() method to provide a handle
     // for a double-check.
-    
+ 
+    private static final Object PRESENT = new Object(); // Dummy value to associate with an Object in the backing Map
     private TreeMap<Long, List<E>> onstack; // object within the stack
-    private HashSet<E> instack; // keeps track which element has been on the stack
+    private ConcurrentHashMap<E, Object> instack; // keeps track which element has been on the stack
     protected int maxsize;
     
     public SortStack(final int maxsize) {
         // the maxsize is the maximum number of entries in the stack
         // if this is set to -1, the size is unlimited
         this.onstack = new TreeMap<Long, List<E>>();
-        this.instack = new HashSet<E>();
+        this.instack = new ConcurrentHashMap<E, Object>();
         this.maxsize = maxsize;
     }
 
@@ -61,7 +62,7 @@ public class SortStack<E> {
      * @param weight
      */
     public void push(final E element, Long weight) {
-        if (!this.instack.add(element)) return;
+        if (this.instack.put(element, PRESENT) != null) return;
         
         // put the element on the stack
         synchronized (this.onstack) {
@@ -147,6 +148,7 @@ public class SortStack<E> {
     
     public boolean bottom(final long weight) {
         // returns true if the element with that weight would be on the bottom of the stack after inserting
+        if (this.onstack.size() == 0) return true;
         Long l;
         synchronized (this.onstack) {
             l = this.onstack.lastKey();

source/net/yacy/kelondro/util/SortStore.java

@@ -27,8 +27,8 @@
 package net.yacy.kelondro.util;
 
 import java.util.ArrayList;
-import java.util.HashSet;
 import java.util.Iterator;
+import java.util.concurrent.ConcurrentHashMap;
 
 /**
  * extends the sortStack in such a way that it adds a list where objects, that had
@@ -38,8 +38,9 @@ import java.util.Iterator;
  */
 public class SortStore<E> extends SortStack<E> {
     
+    private static final Object PRESENT = new Object(); // Dummy value to associate with an Object in the backing Map
     private final ArrayList<stackElement> offstack; // objects that had been on the stack but had been removed
-    private HashSet<E> offset; // keeps track which element has been on the stack or is now in the offstack
+    private ConcurrentHashMap<E, Object> offset; // keeps track which element has been on the stack or is now in the offstack
     private long largest;
     
     public SortStore() {
@@ -50,7 +51,7 @@ public class SortStore<E> extends SortStack<E> {
         super(maxsize);
         this.largest = Long.MIN_VALUE;
         this.offstack = new ArrayList<stackElement>();
-        this.offset = new HashSet<E>();
+        this.offset = new ConcurrentHashMap<E, Object>();
     }
     
     public int size() {
@@ -61,8 +62,9 @@ public class SortStore<E> extends SortStack<E> {
         return this.offstack.size();
     }
 
-    public synchronized void push(final E element, final Long weight) {
-        if (this.offset.contains(element)) return;
+    public void push(final E element, final Long weight) {
+        if (this.offset.containsKey(element)) return;
+        if (super.exists(element)) return;
         super.push(element, weight);
         this.largest = Math.max(this.largest, weight.longValue());
         if (this.maxsize <= 0) return;
@@ -76,21 +78,20 @@ public class SortStore<E> extends SortStack<E> {
      * it is removed and added to the offstack list
      * this is exactly the same as element(offstack.size())
      */
-    public synchronized stackElement pop() {
+    public stackElement pop() {
         final stackElement se = super.pop();
         if (se == null) return null;
+        this.offset.put(se.element, PRESENT);
         this.offstack.add(se);
-        this.offset.add(se.element);
         return se;
     }
     
-    public synchronized stackElement top() {
+    public stackElement top() {
         return super.top();
     }
     
-    public synchronized boolean exists(final E element) {
-        if (super.exists(element)) return true;
-        return this.offset.contains(element);
+    public boolean exists(final E element) {
+        return super.exists(element) || this.offset.containsKey(element);
     }
     
     /**
@@ -100,11 +101,11 @@ public class SortStore<E> extends SortStack<E> {
      * @param position
      * @return
      */
-    public synchronized stackElement element(final int position) {
+    public stackElement element(final int position) {
         if (position < this.offstack.size()) {
             return this.offstack.get(position);
         }
-        if (position >= size()) return null; // we don't have that element
+        if (position >= super.size() + this.offstack.size()) return null; // we don't have that element
         while (position >= this.offstack.size()) this.pop();
         return this.offstack.get(position);
     }
@@ -116,24 +117,26 @@ public class SortStore<E> extends SortStack<E> {
      * @param count
      * @return
      */
-    public synchronized ArrayList<stackElement> list(final int count) {
+    public ArrayList<stackElement> list(final int count) {
         if (count < 0) {
             // shift all elements
-            while (super.size() > 0) this.offstack.add(this.pop());
+            while (super.size() > 0) this.pop();
             return this.offstack;
         }
-        if (size() < count) throw new RuntimeException("list(" + count + ") exceeded avaiable number of elements (" + size() + ")"); 
-        while (this.offstack.size() < count) this.offstack.add(this.pop());
+        if (count > super.size() + this.offstack.size()) throw new RuntimeException("list(" + count + ") exceeded avaiable number of elements (" + size() + ")"); 
+        while (count > this.offstack.size()) this.pop();
         return this.offstack;
     }
     
-    public synchronized void remove(final E element) {
+    public void remove(final E element) {
         super.remove(element);
+        synchronized (this.offstack) {
         Iterator<stackElement> i = this.offstack.iterator();
-        while (i.hasNext()) {
-            if (i.next().element.equals(element)) {
-                i.remove();
-                return;
+            while (i.hasNext()) {
+                if (i.next().element.equals(element)) {
+                    i.remove();
+                    return;
+                }
             }
         }
     }
@@ -150,12 +153,6 @@ public class SortStore<E> extends SortStack<E> {
         a.push("abc", 2L);
         a.push("6s_7dfZk4xvc", 1L);
         a.push("6s_7dfZk4xvc", 1L);
-        a.push("6s_7dfZk4xvc", 1L);
-        a.push("6s_7dfZk4xvc", 1L);
-        a.push("6s_7dfZk4xvc", 1L);
-        a.push("6s_7dfZk4xvc", 1L);
-        a.push("6s_7dfZk4xvc", 1L);
-        a.push("6s_7dfZk4xvc", 1L);
         a.pop();
         System.out.println("size = " + a.size());
     }