Poor performance of '/api/events'

[Stephen Finucane]

I've noticed some poor performance for 'patchwork.ozlabs.org/api/events' when
accessed via a browser or fetched via cURL. I haven't seen similar issues on
any other endpoint and I also can't see anything funky going on with regards to
number of database queries for this endpoint when running Patchwork locally.

Has anyone else seen this issue? I'm away for the next two weeks but if someone
has a chance to look at this in the interim I'd be very appreciative.

Cheers,
Stephen