Andrzej, please also take a look and provide some comments about the user's installation. Maybe there is some problem with config or something else which causes the NPE: message#3983

I found out that cause of this issue was not sending Stats level as FINEST by API script, but it was missed as every time I execute this request it was working fine. Now I added it to request sent by API scrit. But my requests used for testing of this feature were always executed after other/manual request from XMPP client, which sent Stats level as @FINEST@, so questions is:

1. Should this value be cached between requests by component?

2. Should this be cached for everyone or for each user? (now is for every one which may lead to race condition in rare cases)

I would suggest to remove storing value of Stats level between requests (even not requests of same user, possible race condition) in field of component to remove possible race condition and to make each request for statistics using adhoc request statless, which would help testing this feature in future.

I think it does not have to be cached at all, as in theory each request (a correct request) should contain LEVEL value anyway. In fact I find the fact that it cashes LEVEL a bit problematic in some cases.

However, I think, that there should be a default level used in case the request does not contain LEVEL value. As far as I remember this may happen when you double click on the stats component from service discovery in Psi.

The default level should be INFO.

I fixed overwritting default value of Stats Level which was of level INFO only during first execution of adhoc command.