Fix livelock situation in QueryProcessor

[simantics/platform.git] / bundles / org.simantics.db.impl / src / org / simantics / db / impl / query / AsyncReadEntry.java

diff --git a/bundles/org.simantics.db.impl/src/org/simantics/db/impl/query/AsyncReadEntry.java b/bundles/org.simantics.db.impl/src/org/simantics/db/impl/query/AsyncReadEntry.java
index cd5420656400917f5926fa6491b30f27089af6bc..e13ecab72cd0819f71c3c337af62ad242db709c2 100644 (file)
--- a/bundles/org.simantics.db.impl/src/org/simantics/db/impl/query/AsyncReadEntry.java
+++ b/bundles/org.simantics.db.impl/src/org/simantics/db/impl/query/AsyncReadEntry.java
@@ -30,10 +30,10 @@ final public class AsyncReadEntry<T> extends CacheEntryBase<AsyncProcedure<T>> i
 
     private static final Logger LOGGER = LoggerFactory.getLogger(AsyncReadEntry.class);
 
-    protected AsyncRead<T> request;
+    protected AsyncRead<T> id;
 
     AsyncReadEntry(AsyncRead<T> request) {
-        this.request = request;
+        this.id = request;
                if (Development.DEVELOPMENT) {
                        if(Development.<Boolean>getProperty(DevelopmentKeys.CACHE_ENTRY_STATE, Bindings.BOOLEAN)) {
                        System.err.println("[QUERY STATE]: created " + this);
@@ -43,12 +43,12 @@ final public class AsyncReadEntry<T> extends CacheEntryBase<AsyncProcedure<T>> i
 
     @Override
     int makeHash() {
-        return request.hashCode();
+        return id.hashCode();
     }
 
     @Override
     public Object getOriginalRequest() {
-        return request;
+        return id;
     }
 
     @Override
@@ -90,9 +90,9 @@ final public class AsyncReadEntry<T> extends CacheEntryBase<AsyncProcedure<T>> i
                             except(t);
                         }
 
-                    }, request);
+                    }, id);
 
-                    request.perform(graph, proc);
+                    id.perform(graph, proc);
 
                     proc.get();
 
@@ -109,17 +109,17 @@ final public class AsyncReadEntry<T> extends CacheEntryBase<AsyncProcedure<T>> i
 
             @Override
             public int type() {
-                return request.getFlags();
+                return id.getFlags();
             }
 
             @Override
             public String toString() {
-                if (request == null)
+                if (id == null)
                     return "DISCARDED";
                 else if (isExcepted())
-                    return request.toString() + " " + getResult();
+                    return id.toString() + " " + getResult();
                 else
-                    return request.toString() + " " + statusOrException;
+                    return id.toString() + " " + statusOrException;
             }
 
         };
@@ -169,7 +169,14 @@ final public class AsyncReadEntry<T> extends CacheEntryBase<AsyncProcedure<T>> i
             DatabaseException exception;
             
             public AsyncTask(ReadGraphImpl graph) {
+                this(graph, 1);
+            }
+
+            public AsyncTask(ReadGraphImpl graph, int pos) {
                 super(graph);
+                this.position = pos;
+                if(this.position < 1024)
+                    this.position *= 2;
             }
 
             @Override
@@ -213,10 +220,15 @@ final public class AsyncReadEntry<T> extends CacheEntryBase<AsyncProcedure<T>> i
                         }
                         throw new IllegalStateException("Eternal loop in queries.");
                     }
-                    graph.processor.schedule(new AsyncTask(graph));
+                    graph.processor.scheduleLater(new AsyncTask(graph, position));
                 }
             }
             
+            @Override
+            public boolean maybeReady() {
+               return proc.isDone();
+            }
+            
         }
 
         try {
@@ -230,7 +242,7 @@ final public class AsyncReadEntry<T> extends CacheEntryBase<AsyncProcedure<T>> i
         if(needsToBlock) task.run(0);
         else if (proc.isDone()) task.run(0);
         else  {
-            graph.processor.schedule(task);
+            graph.processor.scheduleLater(task);
             return null;
         }
 
@@ -242,11 +254,11 @@ final public class AsyncReadEntry<T> extends CacheEntryBase<AsyncProcedure<T>> i
     @Override
     public String toString() {
         if (isDiscarded())
-            return "DISCARDED " + request.toString();
+            return "DISCARDED " + id.toString();
         else if (isExcepted())
-            return request.toString() + " " + getResult();
+            return id.toString() + " " + getResult();
         else
-            return request.toString() + " " + statusOrException;
+            return id.toString() + " " + statusOrException;
     }
 
     @Override