i'm using nginx1.0.15 stable to serve static files, and with following configurations:

sendfile on;
tcp_nopush on;
tcp_nodelay on;
open_file_cache max=1048000 inactive=604800s;
open_file_cache_min_uses 1;
open_file_cache_valid 3600s;

here is my problem, how can i clear the static file cache without restarting nginx without 'killall -HUP nginx'?