property Element

zero or more 

Specifies a property, which has a name and a value. 

reapIntervalSeconds

60

Specifies the number of seconds between checks for expired sessions for those sessions that are currently swapped out. 

Set this value lower than the frequency at which session data changes is recommended. For example, this value should be as low as possible 1 second for a hit counter servlet on a frequently accessed web site or you could lose the last few hits each time you restart the server. 

directory

directory specified by  

javax.servlet.context

.tempdir context attribute

Specifies the absolute or relative path name of the directory into which individual session files are written. A relative path is relative to the temporary work directory for this web application.