How did you discover this particular query was the problem? You just found it eventually or was there something to actually lead you to it with Kadira or Compose etc.?
I have about 150 concurrent users on only one Galaxy instance and my Compose.io database is bottlenecking and the app is hanging. I’ve added indexes already but one question I have is if you have a collection that needs multiple indexes like so because of the way they’re subscribed to:
Products._ensureIndex({systemId: 1});
Products._ensureIndex({categoryId: 1});
Products._ensureIndex({userId: 1});
Is it better to compound them:
Products._ensureIndex({systemId: 1, categoryId: 1, userId: 1});
Especially if some of the subscriptions actually use two of the fields for querying also? Note my products collection has 17000 documents