performance - How to find queries not using indexes or slow in mongodb

Question

is there a way to find queries in mongodb that are not using Indexes or are SLOW? In MySQL that is possible with the following settings inside configuration file:

log-queries-not-using-indexes = 1
log_slow_queries = /tmp/slowmysql.log

Answer 1

The equivalent approach in MongoDB would be to use the query profiler to track and diagnose slow queries.

With profiling enabled for a database, slow operations are written to the system.profile capped collection (which by default is 1Mb in size). You can adjust the threshold for slow operations (by default 100ms) using the slowms parameter.