The queries are all over the map at around 2,500 per minute. A lot of aggregations and filter operations (There are 471 different elasticsearch calls). Indexing averages a couple hundred per minute.
The documents are generally fairly small (although there are millions of them) and have a couple dozen fields each on average (With the exception of one index that has almost a hundred).
I've looked at copious amounts of memory output from various elasticsearch stats endpoints and everything looks fine besides the heap used number. Cached queries is only in the megabytes. Fielddata is almost 0.
It would be nice if elasticsearch had a "data associated with this index uses 5 GB of heap" endpoint but I haven't found one. I am hopeful that there is one index that is causing trouble that will help isolate the issue.