Long search queries cause Haystack/Elastic error

[antidipyramid]

It seems like this is usually caused by Elastic running out of memory (or at least, it thinks its running out of memory). Example query: Executive Management Committee File Career Pathways.

Some observations:

• this can be replicated locally and on Heroku
• on Heroku we've not even used 1/4 of the available disk space

Since this happens when a search is executed, I suspect this is caused by inefficient queries.

[antidipyramid]

It looks like I can no longer replicate the error with the search string Executive Management Committee File Career Pathways.

We'll keep this one open for a little while in case it resurfaces as January traffic to the site picks up.

[antidipyramid]

2/2 update: For some reason, I can again replicate this error on long search strings. After some testing, it seems like these errors coincide with memory leak-like behavior on the server. We've updated the server to try to mitigate this issue in #1072.