no dht activity for small networks; this is not needed if the network is small

git-svn-id: https://svn.berlios.de/svnroot/repos/yacy/trunk@4062 6c8d7289-2bf4-0310-a012-ef5d649a1542

source/de/anomic/plasma/plasmaSwitchboard.java

@@ -3079,6 +3079,9 @@ public final class plasmaSwitchboard extends serverAbstractSwitch implements ser
         if (yacyCore.seedDB.mySeed.isVirgin()) {
             return "no DHT distribution: status is virgin";
         }
+        if (yacyCore.seedDB.noDHTActivity()) {
+            return "no DHT distribution: network too small";
+        }
         if (getConfig(INDEX_DIST_ALLOW, "false").equalsIgnoreCase("false")) {
             return "no DHT distribution: not enabled";
         }

source/de/anomic/yacy/yacySearch.java

@@ -162,13 +162,15 @@ public class yacySearch extends Thread {
     	//return (yacySeed[]) l.toArray();
     }
     
-    private static yacySeed[] selectDHTPeers(Set wordhashes, int seedcount) {
+    private static yacySeed[] selectSearchTargets(Set wordhashes, int seedcount) {
         // find out a specific number of seeds, that would be relevant for the given word hash(es)
         // the result is ordered by relevance: [0] is most relevant
         // the seedcount is the maximum number of wanted results
         if (yacyCore.seedDB == null) { return null; }
-        if (seedcount > yacyCore.seedDB.sizeConnected()) { seedcount = yacyCore.seedDB.sizeConnected(); }
-
+        if ((seedcount >= yacyCore.seedDB.sizeConnected()) || (yacyCore.seedDB.noDHTActivity())) {
+            seedcount = yacyCore.seedDB.sizeConnected();
+        }
+        
         // put in seeds according to dht
         final kelondroMScoreCluster ranking = new kelondroMScoreCluster();
         final HashMap seeds = new HashMap();
@@ -256,7 +258,7 @@ public class yacySearch extends Thread {
         if (yacyCore.seedDB.mySeed == null || yacyCore.seedDB.mySeed.getPublicAddress() == null) { return null; }
 
         // prepare seed targets and threads
-        final yacySeed[] targetPeers = (clusterselection == null) ? selectDHTPeers(plasmaSearchQuery.hashes2Set(wordhashes), targets) : selectClusterPeers(clusterselection);
+        final yacySeed[] targetPeers = (clusterselection == null) ? selectSearchTargets(plasmaSearchQuery.hashes2Set(wordhashes), targets) : selectClusterPeers(clusterselection);
         if (targetPeers == null) return new yacySearch[0];
         targets = targetPeers.length;
         if (targets == 0) return new yacySearch[0];

source/de/anomic/yacy/yacySeedDB.java

@@ -91,7 +91,8 @@ public final class yacySeedDB {
      * these hashes all shall be generated by base64.enhancedCoder
      */
     public static final int commonHashLength = 12;
-
+    public static final int dhtActivityMagic = 32;
+    
     public static final String[]      sortFields = new String[] {yacySeed.LCOUNT, yacySeed.ICOUNT, yacySeed.UPTIME, yacySeed.VERSION, yacySeed.LASTSEEN};
     public static final String[]   longaccFields = new String[] {yacySeed.LCOUNT, yacySeed.ICOUNT, yacySeed.ISPEED};
     public static final String[] doubleaccFields = new String[] {yacySeed.RSPEED};
@@ -178,6 +179,11 @@ public final class yacySeedDB {
         } catch (IOException e) {}
     }
     
+    public boolean noDHTActivity() {
+        // for small networks, we don't perform DHT transmissions, because it is possible to search over all peers
+        return this.sizeConnected() <= dhtActivityMagic;
+    }
+    
     private synchronized kelondroMapObjects openSeedTable(File seedDBFile) {
         final boolean usetree = false;
         new File(seedDBFile.getParent()).mkdirs();
@@ -800,32 +806,6 @@ public final class yacySeedDB {
         	if (remote != null) try { httpc.returnInstance(remote); } catch (Exception e) {}
         } 	
     }
-        
-    /**
-     * @deprecated Function seems to be unused
-     */
-    public String copyCache(File seedFile, URL seedURL) {
-    	if (seedURL == null) return "COPY - Error: URL not given";
-    	
-    	try {
-    		// getting the current list
-    		ArrayList uv = storeCache(seedFile, true);
-    		
-    		// test download
-    		serverLog.logFine("YACY","Trying to download seed-file '" + seedURL + "'.");
-    		ArrayList check = downloadSeedFile(seedURL);
-    		
-    		// Comparing if local copy and uploaded copy are equal
-    		String errorMsg = checkCache(uv, check);
-    		if (errorMsg == null) {        	        
-    			return "COPY CHECK - Success: the result vectors are equal" + serverCore.crlfString;
-    		} else {
-    			return "COPY CHECK - Error: the result vector is different. " + errorMsg + serverCore.crlfString;
-    		}
-    	} catch (IOException e) {
-    		return "COPY CHECK - Error: IO problem " + e.getMessage() + serverCore.crlfString;
-    	}
-    }
 
     private String checkCache(ArrayList uv, ArrayList check) {                
         if ((check == null) || (uv == null) || (uv.size() != check.size())) {