On 11 February 2010 14:56, Jeffrey Janner <jeffrey.jan...@polydyne.com> wrote: > Also, as I've heard several times here, set the -Xms and -Xmx settings to the > same to improve garbage collect efficiency. (did I interpret that correctly?)
Allocation efficiency - and to make sure you actually get the memory when you need it! If you allocate a small heap initially, then need to expand it later, you have the following potential problems: 1) CPU time to expand the heap - during which your application may be unresponsive, I'm not sure how the modern JVMs work. 2) The system may have overcommitted memory in the meantime, so may need time to flush other data or programs to disk - again, your application may be unresponsive during this time. 3) Most insidiously, if the system's loaded or allocated something that it can't move in the middle of your process' address space, it may be unable to move that. In this case, you won't be able to expand the heap at all - even though there's plenty of free memory in the machine, and you could have had the extra space if you'd asked for it to start with. That's my understanding, anway. Chuck, should I have put my fireproof suit on before posting this? :-) - Peter --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
