The docs here http://docs.mongodb.org/manual/reference/server-status/ say that cursors.timedOut is "[the] total number of cursors that have timed out since the server process started", but I can see dozens of MongoCursorTimeoutException errors (php) scroll by without increasing the count. Is it still sampled/unreliable in 2.2.2?

We have 2 shards of 3 machines each, but only one has a non-zero timedOut value (<10). I will see php report timeouts in bursts of 20-30, for different queries. Can this mean that the timeouts are happening in a way that does not actually hit the server?