Random observations of a very experienced software artist.

    Notes and Sametime performance with JVM Heap Size

    John McCann  September 3 2010 11:41:34 AM
    I was having a problem with Domino Designer in 8.5.2, when I was editing a VERY large script library (LotusScript) and pasted a line of code into it.   Eclipse showed the message about correcting indentation and would do nothing else for minutes at a time.  While researching this problem, I found out two interesting things that might affect you all:

    1) In the eclipse editor, if you are in the mode that displays all the code at once, pasting can be VERY slow.  Switch to the mode that displays a single function or class at once and it will be faster.   At least one user reported this to Lotus as a bug.

    2) JVM Heap Size can dramatically affect performance.   Lotus Notes 8.5 (and Sametime and Designer 8.5) use the JVM virtual machine.  The default settings for Heap Size for my system at 8.5.2 were start with 48M and grow it to 256M.    For my machine with 6GB of memory, this is ridiculously low.   Lots of time is being spent expanding and purging the Java Heap.    I set mine to 1024M for both and 512/256 for Sametime.  As reported on a number of posts from some skilled Notes folks, it noticeably speeds up performance.


    For Notes JVM (and Designer):


    For my system it was

    I changed it to

    I have seen recommendations to make this no more than 1/3 or 1/2 of memory size.  Not being memory constrained, I didn't test which is better.  Never exceed physical RAM or performance will really suffer more than it already does..

    Sametime has a similar properties file which you can change to improve Sametime startup and performance.   It is in
    C:\Program Files\IBM\Lotus\Sametime Connect\rcp\eclipse\plugins\com.ibm.rcp.jcl.desktop.win32.x86_???????????????\jvm.properties

    Not sure what values the question marks will have on your system

    I changed mine to:

    I hope this helps you, it definitely helped me.

    1Juan Medina  10/9/2012 3:55:26 PM  Notes and Sametime performance with JVM Heap Size

    I just read this article your wrote { Link }

    where you mention that increasing heap size for a Sametime environment improved performance ... we have an IBM internal

    environment and my heap size is currently 1024 ... but now I wonder if will be better to increase it as my server has 16GB of memory

    also if you know till what load is recommended to increase it.

    Thanks in advance for your answers and your time