No filter_cache in Elasticsearch 2.2?

We are having trouble with some slow aggregation queries and troubleshooting has guided me in the direction of a possible low filter cache.

Based on this gist, it seems like this was available from different APIs earlier:

I have tried these endpoints, without finding anything related to "filter":


Have also looked in marvel, without finding any reference to the filter cache.

Is it no longer possible to monitor the size of the filter cache?