Why does Reading\Writing\Waiting only grow upwards in Nginx stub status?

Question

Nginx

I displayed the nginx stub status parameters in Zabbix and saw very strange data.
It seems that connections "hang" during the day
dl.dropbox.com/u/937100/screenshots/screen150130-0... A
sharp drop is a restart of nginx.
Are these real connections? Why can they hang like that?

Answer 1

1) picture "nialo"
2) Yes, these are real connections being processed at the moment.
3) For example (the most common reason) - either DDoS by slow clients, or a dumb backend ...

Answer 2

Show how you think this is zabbix. Perhaps the problem is there.

Answer 3

Most counters are just counts, not speed. Count the delta.