My site periodically displays 520 errors.
These errors have been correlated to slow page loads.
I’ve discovered that these errors go away if I disable railgun.
Railgun timeout is set to 100 seconds, and I believe that the default for Cloudflare is 100 seconds yet according to my http access logs the request is completing (returning a 200 code) in less than 70 seconds.
Anyone familiar with the roll Railgun plays in determining timeouts and why disabling Railgun would reduce the frequency of server origin errors?