bundles/org.simantics.db.common/src/org/simantics/db/common/QueryMemoryWatcher.java

   1 package org.simantics.db.common;\r
   2 \r
   3 import org.simantics.db.ReadGraph;\r
   4 import org.simantics.db.service.QueryControl;\r
   5 \r
   6 public class QueryMemoryWatcher {\r
   7 \r
   8     final ReadGraph graph;\r
   9     final QueryControl support;\r
  10     final int stopTime;\r
  11     final long baseline;\r
  12     final long highLimit;\r
  13     final long lowLimit;\r
  14     boolean collecting = false;\r
  15     \r
  16     public QueryMemoryWatcher(ReadGraph graph, int allowedQueries) {\r
  17         this(graph, allowedQueries, 0.5, 10);\r
  18     }\r
  19 \r
  20     public QueryMemoryWatcher(ReadGraph graph, int allowedQueries, double ratio, int stopTime) {\r
  21         this.support = graph.getService(QueryControl.class);\r
  22         baseline = support.count();\r
  23         highLimit = baseline + allowedQueries;\r
  24         lowLimit = baseline + (int)(allowedQueries*ratio);\r
  25         this.graph = graph;\r
  26         this.stopTime = 10;\r
  27         //System.err.println("QueryMemoryWatcher started with " + baseline + " queries.");\r
  28     }\r
  29     \r
  30     public void maintain() {\r
  31         long current = support.count();\r
  32         if(collecting) {\r
  33             if(current > lowLimit) support.gc(graph, stopTime);\r
  34             else {\r
  35 //                System.err.println("QueryMemoryWatcher stops collecting");\r
  36                 collecting = false;\r
  37             }\r
  38         } else {\r
  39             if(current > highLimit) {\r
  40 //                System.err.println("QueryMemoryWatcher starts collecting");\r
  41                 collecting = true;\r
  42             }\r
  43         }\r
  44     }\r
  45     \r
  46 }\r