Not sure is this a bug or not.
In this chart http://localhost/monitoring?part=graph&graph=httpSessions, I see the HTTP session count is increased from 0 to 100,110,120... after restart. But in this page http://localhost/monitoring?part=sessions I only see less than 10 sessions.
I think the data of the 2 charts should be aligned, is it correct?

Btw, for the HTTP session is always increased, I think it's an issue and just post in community to get help http://jenkins-ci.361315.n4.nabble.com/HTTP-session-increases-and-out-of-memory-td4680122.html