I'm trying to unmarshal a knowledge session that has been persisted to file, but I get the following exception: Stack Trace: com.google.protobuf.InvalidProtocolBufferException: Protocol message was too large. May be malicious. Use CodedInputStream.setSizeLimit() to increase the size limit. at com.google.protobuf.InvalidProtocolBufferException.sizeLimitExceeded:89 at com.google.protobuf.CodedInputStream.refillBuffer:720 at com.google.protobuf.CodedInputStream.isAtEnd:666 at com.google.protobuf.CodedInputStream.readTag:99 at org.drools.marshalling.impl.ProtobufMessages$Header$Builder.mergeFrom:967 at org.drools.marshalling.impl.ProtobufMessages$Header$Builder.mergeFrom:773 at com.google.protobuf.AbstractMessageLite$Builder.mergeFrom:212 at com.google.protobuf.AbstractMessage$Builder.mergeFrom:746 at org.drools.marshalling.impl.ProtobufMessages$Header.parseFrom:724 at org.drools.marshalling.impl.PersisterHelper.readFromStreamWithHeader:234 at org.drools.marshalling.impl.ProtobufInputMarshaller.loadAndParseSession:217 at org.drools.marshalling.impl.ProtobufInputMarshaller.readSession:107 at org.drools.marshalling.impl.ProtobufMarshaller.unmarshall:143 The session consists of >1M facts, and the file is ~167 MB in size. While Googling, I stumbled upon the recommendation to run CodedInputStream.resetSizeCounter() inbetween deserializing messages. Is this a fix that could be implemented in Drools? Is there any way of configuring or parameterizing the unmarshalling size limit used by Drools?