I have an image resize server sitting behind an nginx server.
On a cold cache two clients requesting the same file could trigger two resize jobs.
client-01.net GET /resize.do/avatar-1234567890/300x200.png client-02.net GET /resize.do/avatar-1234567890/300x200.png
It would be great if only one of the requests could go through to the backend in this situation (while the other client is set 'on-hold').
In Varnish there seems to be such a feature, called Request Coalescing. However that seems to be a Varnish-specific term. Is there something similar for Nginx?