proxy_cache and restarts

[Resicow]

Hello,

I have a question on for nginx handles restarts and proxy_cache.

Say I have 2 million objects cached, taking up 50GBs of space. Then I 
get a kernel panic or some other error, and have to restart the physical 
machine.

When I start nginx up again the 2 million objects are still on the disk, 
but nginx no longer has its internal caching table, correct? Are those 
files just stuck on the disk forever, or do I need to ensure the cache 
is empty if nginx needs to be restarted by manually deleting the objects?

Also on binary upgrades, will the internal proxy cache table survive?

Thanks,

John