Okay, I updated to the latest driver and it really caused issues for me. I have no idea what is going on but will describe the situation.

I have a collection for logging called "main". In my application I create two connections. I do this because in production I have "main" on a separate db.

Basically, what happens is when I first start my application I can query my logs doing this:

this.logConn('main', function (err, collection) {
console.log('collection', collection.s.name);
collection.find(findObject)
.sort(

{ts: -1}

)
.skip(skip)
.limit(limit)
.toArray(function(err, docs)

{ console.log('HERE'); callback(false, docs ); }

);
});

Then after about 3 minutes of not being used (this seems important, if I sit this and refresh the web page that causes the query it seems to keep working), after I come back, it stops working. I never get anything back, even an error. After enabling error logging on the drover this is what I get:

Connection 1464375720617
connection 3 for [ds043220.mongolab.com:43220] timed out
Pool 1464375720617
pool [undefined] timed out [

{"name":"MongoError","message":"connection 3 to ds043220.mongolab.com:43220 timed out"}

] with connection [

{"id":3,"host":"ds043220.mongolab.com","port":43220}

]
Server 1464375720617
Connection 1464375720618
connection 3 with for [ds043220.mongolab.com:43220] closed
Pool 1464375720618
pool [undefined] closed [

{"name":"MongoError","message":"connection 3 to ds043220.mongolab.com:43220 closed"}

] with connection [

{"id":3,"host":"ds043220.mongolab.com","port":43220}

]
Connection 1464375721619
creating connection 4 with options [

{"host":"ds043220.mongolab.com","port":43220,"size":5,"connectionTimeout":120000,"socketTimeout":120000}

]
Server 1464375721622

It shows in the logs that it reconnects BUT every time I query with this connection it does the same thing. It's unusable until I restart the service.

I switched back to 2.1.18 (becaues that seemed like the last major release) and it works just fine.

This only happens when querying this single collection. This collection has a lot of very LARGE records, I wonder if that is related. It's also one of the few collections I do a sort, skip, and limit on too.