Igor:
As I explained to francis ( https://forum.nginx.org/read.php?2,275138,275163#msg-275163 ), I don't want to cache what goes to uwsgi.
I get a request for /v/example-uri, my back-end answers with X-accel-redirect: /nfs/file1.img (2gb).
I want nginx to copy this to a local cache ( /cache/c/29/b7f54b2df7773722d382f4809d65029c or whatever ) and serve subsequent requests (that might be /v/example-7-uri or /v/qwoeiuqwoeiq but get the same response X-accel-redirect: /nfs/file1.img) from the cache.
David