Project language page times out on large projects

Summary

The charts page takes a long time to generate, and the data fetched is not fetched. Especially the project languages are taking a long time to generate, and only cached by linguist if the run was completed in full. If unicorn kills the connection after 60s, this is not the case.

Steps to reproduce

Upload the linux kernel, and visit the page. Or gitlab-design: https://gitlab.com/gitlab-org/gitlab-design/graphs/master/charts

What is the current bug behavior?

Page times out, 500 status code

What is the expected correct behavior?

I see a page in < 5s

Relevant

gitaly#626 (closed)