diff --git a/htroot/IndexControlRWIs_p.java b/htroot/IndexControlRWIs_p.java
index 7b1f59658..19b05b2b0 100644
--- a/htroot/IndexControlRWIs_p.java
+++ b/htroot/IndexControlRWIs_p.java
@@ -731,7 +731,7 @@ public class IndexControlRWIs_p
         final QueryParams query =
             new QueryParams(ASCII.String(keyhash), -1, filter, segment, sb.getRanking(), "IndexControlRWIs_p");
         final ReferenceOrder order = new ReferenceOrder(query.ranking, UTF8.getBytes(query.targetlang));
-        final RWIProcess ranked = new RWIProcess(query, order, Integer.MAX_VALUE, false);
+        final RWIProcess ranked = new RWIProcess(query, order, false);
         ranked.run();
 
         if ( ranked.filteredCount() == 0 ) {
diff --git a/source/net/yacy/cora/services/federated/SearchResult.java b/source/net/yacy/cora/services/federated/SearchResult.java
index c0c9e19dd..028356619 100644
--- a/source/net/yacy/cora/services/federated/SearchResult.java
+++ b/source/net/yacy/cora/services/federated/SearchResult.java
@@ -31,7 +31,7 @@ import net.yacy.cora.sorting.WeakPriorityBlockingQueue;
 public class SearchResult extends WeakPriorityBlockingQueue<Object> {
 
     public SearchResult(final int maxsize) {
-        super(maxsize);
+        super(maxsize, true);
     }
 
     private static final long serialVersionUID = -4865225874936938082L;
@@ -64,6 +64,7 @@ public class SearchResult extends WeakPriorityBlockingQueue<Object> {
         return this.maxScore;
     }
 
+    @Override
     public String toString() {
         return "{count=" + this.numFound + ", offset=" + this.start + (this.maxScore != null ? ", maxScore=" + this.maxScore : "") + ", docs=" + super.toString() + "}";
     }
diff --git a/source/net/yacy/cora/sorting/WeakPriorityBlockingQueue.java b/source/net/yacy/cora/sorting/WeakPriorityBlockingQueue.java
index a240c3238..5279e3256 100644
--- a/source/net/yacy/cora/sorting/WeakPriorityBlockingQueue.java
+++ b/source/net/yacy/cora/sorting/WeakPriorityBlockingQueue.java
@@ -53,11 +53,11 @@ public class WeakPriorityBlockingQueue<E> {
      * weights that are preferred are returned first when a pop from the stack is made
      * @param maxsize the maximum size of the stack. When the stack exceeds this number, then entries are removed
      */
-    public WeakPriorityBlockingQueue(final int maxsize) {
+    public WeakPriorityBlockingQueue(final int maxsize, boolean drain) {
         // the maxsize is the maximum number of entries in the stack
         // if this is set to -1, the size is unlimited
         this.queue = new TreeSet<Element<E>>();
-        this.drained = new ArrayList<Element<E>>();
+        this.drained = drain ? new ArrayList<Element<E>>() : null;
         this.enqueued = new Semaphore(0);
         this.maxsize = maxsize;
     }
@@ -66,7 +66,7 @@ public class WeakPriorityBlockingQueue<E> {
      * clear the queue
      */
     public synchronized void clear() {
-        this.drained.clear();
+        if (this.drained != null) this.drained.clear();
         this.queue.clear();
         this.enqueued.drainPermits();
     }
@@ -76,7 +76,7 @@ public class WeakPriorityBlockingQueue<E> {
      * @return true if the queue is empty, false if not
      */
     public boolean isEmpty() {
-        return this.queue.isEmpty() & this.drained.isEmpty();
+        return this.queue.isEmpty() & (this.drained == null || this.drained.isEmpty());
     }
 
     /**
@@ -94,7 +94,7 @@ public class WeakPriorityBlockingQueue<E> {
      * @return
      */
     public synchronized int sizeDrained() {
-        return this.drained.size();
+        return this.drained == null ? 0 : this.drained.size();
     }
 
     /**
@@ -103,7 +103,9 @@ public class WeakPriorityBlockingQueue<E> {
      * @return
      */
     public synchronized int sizeAvailable() {
-        return Math.min(this.maxsize, this.queue.size() + this.drained.size());
+        return this.maxsize < 0 ?
+                        this.queue.size() + (this.drained == null ? 0 : this.drained.size()) :
+                        Math.min(this.maxsize, this.queue.size() + (this.drained == null ? 0 : this.drained.size()));
     }
 
     /**
@@ -116,7 +118,7 @@ public class WeakPriorityBlockingQueue<E> {
      */
     public synchronized void put(final Element<E> element) {
         // put the element on the stack
-        if (this.drained.contains(element)) return;
+        if (this.drained != null && this.drained.contains(element)) return;
         if (this.queue.size() == this.maxsize) {
             // remove last elements if stack is too large
             if (this.queue.add(element)) this.queue.remove(this.queue.last());
@@ -170,7 +172,7 @@ public class WeakPriorityBlockingQueue<E> {
         final Element<E> element = this.queue.first();
         assert element != null;
         this.queue.remove(element);
-        if (this.drained.size() < this.maxsize) this.drained.add(element);
+        if (this.drained != null && (this.maxsize == -1 || this.drained.size() < this.maxsize)) this.drained.add(element);
         assert this.queue.size() >= this.enqueued.availablePermits() : "(take) queue.size() = " + this.queue.size() + ", enqueued.availablePermits() = " + this.enqueued.availablePermits();
         return element;
     }
@@ -197,6 +199,7 @@ public class WeakPriorityBlockingQueue<E> {
      * @return the element from the recorded position or null if that position is not available
      */
     public Element<E> element(final int position) {
+        if (this.drained == null) return null;
         if (position < this.drained.size()) {
             return this.drained.get(position);
         }
@@ -225,6 +228,7 @@ public class WeakPriorityBlockingQueue<E> {
      * @throws InterruptedException
      */
     public Element<E> element(final int position, long time) throws InterruptedException {
+        if (this.drained == null) return null;
         long timeout = System.currentTimeMillis() + time;
         if (position < this.drained.size()) {
             return this.drained.get(position);
@@ -246,6 +250,7 @@ public class WeakPriorityBlockingQueue<E> {
      * @return a list of elements in the stack
      */
     public synchronized ArrayList<Element<E>> list(final int count) {
+        if (this.drained == null) return null;
         if (count < 0) {
             return list();
         }
@@ -259,6 +264,7 @@ public class WeakPriorityBlockingQueue<E> {
      * @return a list of all elements in the stack
      */
     public synchronized ArrayList<Element<E>> list() {
+        if (this.drained == null) return null;
         // shift all elements
         while (!this.queue.isEmpty()) this.poll();
         return this.drained;
@@ -269,6 +275,7 @@ public class WeakPriorityBlockingQueue<E> {
      * @return an iterator over all drained positions.
      */
     public synchronized Iterator<Element<E>> iterator() {
+        if (this.drained == null) return null;
         // shift all elements to the offstack
         while (!this.queue.isEmpty()) this.poll();
         return this.drained.iterator();
@@ -377,7 +384,7 @@ public class WeakPriorityBlockingQueue<E> {
     }
 
     public static void main(String[] args) {
-        final WeakPriorityBlockingQueue<String> a = new WeakPriorityBlockingQueue<String>(3);
+        final WeakPriorityBlockingQueue<String> a = new WeakPriorityBlockingQueue<String>(3, true);
         //final Element<String> REVERSE_POISON = new ReverseElement<String>("", Long.MIN_VALUE);
         new Thread(){
             @Override
diff --git a/source/net/yacy/search/index/DocumentIndex.java b/source/net/yacy/search/index/DocumentIndex.java
index 783f54c43..a25763844 100644
--- a/source/net/yacy/search/index/DocumentIndex.java
+++ b/source/net/yacy/search/index/DocumentIndex.java
@@ -45,7 +45,6 @@ import net.yacy.kelondro.data.meta.URIMetadataRow;
 import net.yacy.kelondro.logging.Log;
 import net.yacy.search.query.QueryParams;
 import net.yacy.search.query.RWIProcess;
-import net.yacy.search.query.SearchEvent;
 import net.yacy.search.ranking.RankingProfile;
 import net.yacy.search.ranking.ReferenceOrder;
 
@@ -223,7 +222,7 @@ public class DocumentIndex extends Segment
         final QueryParams query =
             new QueryParams(querystring, count, null, this, textRankingDefault, "DocumentIndex");
         final ReferenceOrder order = new ReferenceOrder(query.ranking, UTF8.getBytes(query.targetlang));
-        final RWIProcess rankedCache = new RWIProcess(query, order, SearchEvent.max_results_preparation, false);
+        final RWIProcess rankedCache = new RWIProcess(query, order, false);
         rankedCache.start();
 
         // search is running; retrieve results
diff --git a/source/net/yacy/search/query/RWIProcess.java b/source/net/yacy/search/query/RWIProcess.java
index c2aafb61b..43b189c7e 100644
--- a/source/net/yacy/search/query/RWIProcess.java
+++ b/source/net/yacy/search/query/RWIProcess.java
@@ -44,6 +44,7 @@ import net.yacy.cora.document.Classification.ContentDomain;
 import net.yacy.cora.document.MultiProtocolURI;
 import net.yacy.cora.lod.SimpleVocabulary;
 import net.yacy.cora.protocol.Scanner;
+import net.yacy.cora.services.federated.yacy.CacheStrategy;
 import net.yacy.cora.sorting.ClusteredScoreMap;
 import net.yacy.cora.sorting.ConcurrentScoreMap;
 import net.yacy.cora.sorting.ScoreMap;
@@ -73,7 +74,7 @@ public final class RWIProcess extends Thread
 {
 
     private static final long maxWaitPerResult = 300;
-    private static final int maxDoubleDomAll = 1000, maxDoubleDomSpecial = 10000;
+    private static final int max_results_preparation = 3000, max_results_preparation_special = -1; // -1 means 'no limit'
 
     private final QueryParams query;
     private final HandleSet urlhashes; // map for double-check; String/Long relation, addresses ranking number (backreference for deletion)
@@ -109,13 +110,13 @@ public final class RWIProcess extends Thread
     private final ScoreMap<String> filetypeNavigator; // a counter for file types
     private final Map<String, ScoreMap<String>> vocabularyNavigator; // counters for Vocabularies
 
-    public RWIProcess(final QueryParams query, final ReferenceOrder order, final int maxentries, final boolean remote) {
+    public RWIProcess(final QueryParams query, final ReferenceOrder order, final boolean remote) {
         // we collect the urlhashes and construct a list with urlEntry objects
         // attention: if minEntries is too high, this method will not terminate within the maxTime
         // sortorder: 0 = hash, 1 = url, 2 = ranking
         this.addRunning = true;
         this.localSearchInclusion = null;
-        this.stack = new WeakPriorityBlockingQueue<WordReferenceVars>(maxentries);
+        this.stack = new WeakPriorityBlockingQueue<WordReferenceVars>(query.snippetCacheStrategy == null || query.snippetCacheStrategy == CacheStrategy.CACHEONLY ? max_results_preparation_special : max_results_preparation, false);
         this.doubleDomCache = new ConcurrentHashMap<String, WeakPriorityBlockingQueue<WordReferenceVars>>();
         this.query = query;
         this.order = order;
@@ -499,7 +500,7 @@ public final class RWIProcess extends Thread
                         m = this.doubleDomCache.get(hosthash);
                         if ( m == null ) {
                             // first appearance of dom. we create an entry to signal that one of that domain was already returned
-                            m = new WeakPriorityBlockingQueue<WordReferenceVars>(this.query.specialRights ? maxDoubleDomSpecial : maxDoubleDomAll);
+                            m = new WeakPriorityBlockingQueue<WordReferenceVars>(this.query.snippetCacheStrategy == null || this.query.snippetCacheStrategy == CacheStrategy.CACHEONLY ? max_results_preparation_special : max_results_preparation, false);
                             this.doubleDomCache.put(hosthash, m);
                             return rwi;
                         }
@@ -552,15 +553,16 @@ public final class RWIProcess extends Thread
 
         // finally remove the best entry from the doubledom cache
         m = this.doubleDomCache.get(bestEntry.getElement().hosthash());
-        bestEntry = m.poll();
-        if (m.sizeAvailable() == 0) {
-            synchronized ( this.doubleDomCache ) {
-                if (m.sizeAvailable() == 0) {
-                    this.doubleDomCache.remove(bestEntry.getElement().hosthash());
+        if (m != null) {
+            bestEntry = m.poll();
+            if (bestEntry != null && m.sizeAvailable() == 0) {
+                synchronized ( this.doubleDomCache ) {
+                    if (m.sizeAvailable() == 0) {
+                        this.doubleDomCache.remove(bestEntry.getElement().hosthash());
+                    }
                 }
             }
         }
-
         return bestEntry;
     }
 
diff --git a/source/net/yacy/search/query/SearchEvent.java b/source/net/yacy/search/query/SearchEvent.java
index 02de72095..dc5e76723 100644
--- a/source/net/yacy/search/query/SearchEvent.java
+++ b/source/net/yacy/search/query/SearchEvent.java
@@ -82,8 +82,6 @@ public final class SearchEvent
         RESULTLIST;
     }
 
-    public static final int max_results_preparation = 420000;
-
     // class variables that may be implemented with an abstract class
     private long eventTime;
     private QueryParams query;
@@ -147,7 +145,7 @@ public final class SearchEvent
 
         // initialize a ranking process that is the target for data
         // that is generated concurrently from local and global search threads
-        this.rankingProcess = new RWIProcess(this.query, this.order, max_results_preparation, remote);
+        this.rankingProcess = new RWIProcess(this.query, this.order, remote);
 
         // start a local search concurrently
         this.rankingProcess.start();
diff --git a/source/net/yacy/search/query/SnippetProcess.java b/source/net/yacy/search/query/SnippetProcess.java
index ed8151973..da31d9404 100644
--- a/source/net/yacy/search/query/SnippetProcess.java
+++ b/source/net/yacy/search/query/SnippetProcess.java
@@ -109,8 +109,8 @@ public class SnippetProcess {
 
         this.urlRetrievalAllTime = 0;
         this.snippetComputationAllTime = 0;
-        this.result = new WeakPriorityBlockingQueue<ResultEntry>(Math.max(1000, 10 * query.itemsPerPage())); // this is the result, enriched with snippets, ranked and ordered by ranking
-        this.images = new WeakPriorityBlockingQueue<MediaSnippet>(Math.max(1000, 10 * query.itemsPerPage()));
+        this.result = new WeakPriorityBlockingQueue<ResultEntry>(Math.max(1000, 10 * query.itemsPerPage()), true); // this is the result, enriched with snippets, ranked and ordered by ranking
+        this.images = new WeakPriorityBlockingQueue<MediaSnippet>(Math.max(1000, 10 * query.itemsPerPage()), true);
 
         // snippets do not need to match with the complete query hashes,
         // only with the query minus the stopwords which had not been used for the search