Orientdb Java Heap Error

I ran a test on Orientdb 2.2.10 using Transnational graph

With the following Sudo code on single thread system

   for(i = 1 to 1000)
{
    DB_Name = getRandomString()

    createGraphDb(DB_Name ) using OServerAdmin : if db do not exist
    gFactory = OrientGraphFactory(DB_Name ) : if db exist


    graph = OrientGraphFactory.getTx()
    previousEvent = null

    for(j=1 to 1000)
      {
        currentEvent = getrandomString()
        if(previousEvent and currentEvent != null)
              {
                   - create Vertex named currentVertex and edges between them 
                   - (from previous to current event)
              }
        else
              {
                    create vertex named current event 
              }
         previousEvent = currentEvent
      }
   graph.shutdown()

}

I got the the following Exception after few iteration of my outer loop.

Exception in thread "Thread-0" java.lang.OutOfMemoryError: Java heap space
at java.util.Arrays.copyOfRange(Unknown Source)
at java.lang.String.<init>(Unknown Source)
at java.lang.String.substring(Unknown Source)
at java.lang.String.split(Unknown Source)
at java.lang.String.split(Unknown Source)
at com.orientechnologies.orient.core.config.OStorageConfiguration.fromStream(OStorageConfiguration.java:268)
at com.orientechnologies.orient.core.config.OStorageConfiguration.fromStream(OStorageConfiguration.java:497)
at com.orientechnologies.orient.core.config.OStorageConfiguration.load(OStorageConfiguration.java:207)
at com.orientechnologies.orient.client.remote.OStorageRemote.open(OStorageRemote.java:330)
at com.orientechnologies.orient.core.db.document.ODatabaseDocumentTx.open(ODatabaseDocumentTx.java:257)
at com.orientechnologies.orient.core.db.OPartitionedDatabasePool$DatabaseDocumentTxPooled.internalOpen(OPartitionedDatabasePool.java:445)
at com.orientechnologies.orient.core.db.OPartitionedDatabasePool.openDatabase(OPartitionedDatabasePool.java:308)
at com.orientechnologies.orient.core.db.OPartitionedDatabasePool.acquire(OPartitionedDatabasePool.java:263)
at com.tinkerpop.blueprints.impls.orient.OrientBaseGraph.<init>(OrientBaseGraph.java:144)
at com.tinkerpop.blueprints.impls.orient.OrientTransactionalGraph.<init>(OrientTransactionalGraph.java:78)
at com.tinkerpop.blueprints.impls.orient.OrientGraph.<init>(OrientGraph.java:135)
at com.tinkerpop.blueprints.impls.orient.OrientGraphFactory.getTx(OrientGraphFactory.java:119)

Is their any problem with my sudo code or with OrientDb.

If their exist any better way, kindly please suggest.

Thanks..!

How many gigs of ram do you have available? For example if you can assign maximum 8GB to the Java process, it's usually better assigning small heap and large disk cache buffer (off-heap memory). So rather than:

java -Xmx8g ...

You could instead try this:

java -Xmx800m -Dstorage.diskCache.bufferSize=7200 ...

For further details you can read the page regarding performance tuning on official documentation.

Hope it helps.