Kirill Kireyev <kir...@instagrok.com> wrote:
>Thanks for all your thorough advice Shanti! (and everyone else) > >Here are my findings so far: >0) My servlet sessions store a large number (~10s of M) or data in RAM. > >This is by design, to optimize performance. I can also have ~3K active >sessions at any one time. Hence a large heap size. >1) When I (1) manually expire inactive sessions through Tomcat web >interface and (2) manually hit "Perform GC" through jvisualvm console >attached to the tomcat process, everything works great, and the memory >is successfully reclaimed, and the used heap size drops back to what >it >should be when the application initializes. >2) However, this doesn't seem to work automatically. More specifically: > a) Sessions are not expiring without manually doing it (I can see >the number growing in the Tomcat web interface). Even though my >conf/web.xml says: > <session-config> > <session-timeout>20</session-timeout> > </session-config> > b) A full garbage collection is not being performed unless I do it >manually. I'm attaching the GC records from my logs/catalina.out. > >Any insights? Session expiration is performed by the background processing thread. What is that thread doing (a thread dump - well several over time - will tell you). Fix the session expiration issue and the GC issue will be solved. Note the JVM may well not perform a full GC unless it absolutely has to. In fact, the JVM may not perform any GC if it doesn't have to. Mark --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
