Pass CORRELATION_ID env variable to resize image subprocesses
This injects the CORRELATION_ID
env variable into image resizer processes.
This allows us to determine which request was responsible for a given image resizer call. As a last resort this can be quite useful, as has been shown with the addition of this mechanism to gitaly (gitaly!2478 (merged)).
Example usage:
sudo cat /proc/$(pgrep -n -f 'gitlab-resize-image')/environ | tr '\0' '\n'
This may help us diagnose issues in production, see also: gitlab-com/runbooks!2788 (merged).