}
public boolean updateSourceLog(ISource src, int retention) {
MongoDBCollection coll = new MongoDBCollection(db,"sources_log");
coll.createIndex("id_source", false);
coll.createIndex("createtime", false);
BasicDBObject doc = new BasicDBObject();
doc.put("id_source", src.getId());
doc.put("createtime", new Date().getTime());
doc.put("log",src.memLogGet());