I had trouble in below situation. Cache file unexpected shared.

• plural monitoring with different pattern
• use cache
• use same state directory

My understanding about current sisuation are...

• seek file, cache file are created under the state directory
• seek file name: unique per log file path + i-node. ( when tag is passed, log file path + i-node + tag )
• cache file name: fixed. ( when tag is passed, unique per tag )

Proposal

Unexpected cache file shareing caused critical problem,
so cache file name should be safe by default.

I think safe way is that each pattern + log file path has uniqe state directory,
but check_log_ng use same state directory in some situation...