Question

I am using mongodb to store user’s events, there’s a document for every user, containing an array of events. The system processes thousands of events a minute and inserts each one of them to mongo.

The problem is that I get poor performance for the update operation, using a profiler, I notice that the WriteResult.getError is the one that incur the performance impact.

That makes sense, the update is async, but if one wants to retrieve the operation result he needs to wait until the operation is completed.

My question, is there a way to keep the update async, but only get an exception if error occurs (99.999 of the times there is no error, so the system waits for nothing). I understand it means the exception will be raised somewhere further down the process flow, but I can live with that.

Any other suggestions?

The application is written in Java so we’re using the Java driver, but I am not sure it’s related.

Answer 1

have you done indexing on your records?
it may be a problem to your performance.

if not done before you should do Indexing on ur collection like

db.collectionName.ensureIndex({"event.type":1})  

for more help visit http://www.mongodb.org/display/DOCS/Indexes