massive deleted open files in proxy cache

[patademahesh]

We are facing the same issue. File gets deleted but it holds the FD and disk
space is never released until we restart the nginx server. Most of the files
we is from proxy_temp_path directory. This is causing filesystem to go out
of space. We tried this with tmpfs and normal disk.

Posted at Nginx Forum: https://forum.nginx.org/read.php?2,272519,287604#msg-287604