From 09ba6814c0e6e126180482c66e9cb8a6b5f5bd46 Mon Sep 17 00:00:00 2001
From: orbiter <orbiter@6c8d7289-2bf4-0310-a012-ef5d649a1542>
Date: Thu, 26 May 2011 12:58:11 +0000
Subject: [PATCH] - non-blocking word hash computation with dynamic digest
 object generation (this was important!) - (very) small performance
 enhancement in did-you-mean

git-svn-id: https://svn.berlios.de/svnroot/repos/yacy/trunk@7740 6c8d7289-2bf4-0310-a012-ef5d649a1542
---
 source/de/anomic/data/DidYouMean.java      |  2 +-
 source/net/yacy/kelondro/order/Digest.java | 14 ++++++++++++--
 2 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/source/de/anomic/data/DidYouMean.java b/source/de/anomic/data/DidYouMean.java
index 12defa1b9..366610314 100644
--- a/source/de/anomic/data/DidYouMean.java
+++ b/source/de/anomic/data/DidYouMean.java
@@ -356,7 +356,7 @@ public class DidYouMean {
             public void run() {
                 String s;
                 try {
-                    while (!(s = guessLib.take()).equals(POISON_STRING)) {
+                    while ((s = guessLib.take()) != POISON_STRING) {
                         if (s.length() >= MinimumOutputWordLength && index.has(Word.word2hash(s))) resultSet.add(s);
                         if (System.currentTimeMillis() > timeLimit) return;
                     }
diff --git a/source/net/yacy/kelondro/order/Digest.java b/source/net/yacy/kelondro/order/Digest.java
index 4d5dc592b..1958252ad 100644
--- a/source/net/yacy/kelondro/order/Digest.java
+++ b/source/net/yacy/kelondro/order/Digest.java
@@ -50,7 +50,7 @@ import net.yacy.kelondro.logging.Log;
 
 public class Digest {
 	
-    private final static int digestThreads = Runtime.getRuntime().availableProcessors() * 2 + 1;
+    private final static int digestThreads = Runtime.getRuntime().availableProcessors() * 4;
 	public static BlockingQueue<MessageDigest> digestPool = new ArrayBlockingQueue<MessageDigest>(digestThreads);
 	static {
 		for (int i = 0; i < digestThreads; i++)
@@ -115,7 +115,17 @@ public class Digest {
     public static byte[] encodeMD5Raw(final String key) {
     	MessageDigest digest = null;
     	boolean fromPool = true;
-        try {
+    	if (digestPool.size() == 0) {
+    	    // if there are no digest objects left, create some on the fly
+    	    // this is not the most effective way but if we wouldn't do that the encoder would block
+    	    try {
+                digest = MessageDigest.getInstance("MD5");
+                digest.reset();
+                fromPool = false;
+            } catch (NoSuchAlgorithmException e) {
+            }
+    	}
+        if (digest == null) try {
             digest = digestPool.take();
         } catch (InterruptedException e) {
         	Log.logWarning("Digest", "using generic instead of pooled digest");