Hi Andre, > So I am not objecting to using 3000 MB of Heap, I am just curious. > If someone like Eric Robinson can run a non-trivial multi-user Tomcat > application with an average 64 MB of Heap and you can do pretty much the > same, then I am curious as to which Tomcat application (or situation) may > require 3,000 MB of Heap, which is 50 times more.
I will give you an example of two reasons for a large heap - (1) You host a large data set that you treat as a global in memory database achieving lighting quick sorts and filters across any column. This consumes a large amount of memory for the life of the JVM. Daily refreshes require double space in transition. The size of the heap will limit the size of the data set. (2) You need to produce large Excel spreadsheets or Powerpoint decks using Apache POI. Due to the binary nature of the file formats everything is constructed in memory and the memory footprint of the Java objects is much larger. The XML versions don't give you any relief as they are Zip files. This means you need large amounts of space for short periods of time. Again more memory means the more head room you have for these requests. You have to know your app well to know if you have enough room for the very occasional large request. If that can be too big then you will need to build an execution queue of some type behind your web app. Regards, Dave --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
