Proxy cache zone maximal size

[footplus]

Hello,

When using nginx in proxy_cache mode, and configuring the cache zone like
below, it seems that the zone sometimes exceed the configured size by like
10%; I'm buffering new items at a high rate, and I'm wondering how this
cache zone is cleaned up ? Is there a time-based recurring size check ? or
another mechanism ?

I also noticed that the cache doesn't seem to be cleaned before the cache
loader process has completed all the cache items. Is this a normal behavior
? 

My goal is to set the max_size to a "safe" value, to ensure that the cache
space is never saturated.

proxy_cache_path /run/store keys_zone=cache-memory:500m
		levels=1:1:1
		max_size=60g
		use_temp_path=off
		inactive=8h;

Thanks !
Best regards,
Aurélien

Posted at Nginx Forum: https://forum.nginx.org/read.php?2,262459,262459#msg-262459