Collect scheduling information for all the threads.

Change-Id: I9b6cebc7eb3dfa6de22a46e287185180df78281c
Reviewed-on: http://review.couchbase.org/36331
Tested-by: Aliaksey Artamonau <aliaksiej.artamonau@gmail.com>
Reviewed-by: Artem Stemkovski <artem@couchbase.com>