Updated 10. April 2016 to reflect the default garbage collector change in Java 9:
throughout the last year I have been fine-tuning SQ by the various Java (which SQ runs on) options that you can pass on to it during start-up. I am now satisfied with the performance and on the same side heavy reduction in memory usage that I´ve achieved through fine-tuning the Java options.
Just use this line to launch SQ with max performance and as low as possible memory usage:
StrategyQuant64.exe -J-server -J-Xmx13g -J-XX:+DisableExplicitGC -J-XX:+AggressiveOpts -J-XX:+UseSerialGC
^^ please adjust the "-J-Xmx13g" to the memory you want to assign to SQ (and which you really have free!) as max allowed amount. E.g. if you want to allow it 6GB max, use "-J-Xmx6g" instead.
Additionally to this launch-line, I´d also recommend to replace the JVM from Oracle to the one from Zulu, you will get even more speed and less RAM usage with this one as it is a straight build of the OpenJDK sources (the original Java) without Oracles branding and other things added to it. You can get it here: http://www.azulsyste.../zulu/downloads . There also currently is a dedicated page for the new Java 9 beta which also works fine and is even faster than Java 8, but only up to version 184.108.40.206 since changes in Java 9 that have been adapted in later builds won´t work anymore with SQ 3.8.1, you can download it here: http://cdn.azul.com/...0.0-win_x64.zip .
Just install it and afterwards rename the directory "j64" in your StrategyQuant directory to "j64.old". Create a new "j64" directory and copy the complete Zulu installation (usually from C:\Program Files\Java.....) into the newly created "j64" directory.
Please compare on your own how SQ runs without any parameters and with my command line and the JVM replaced. You´ll see that when starting to build strategies that alone in the first 2 minutes of building RAM usage will be half with my command line than SQ without my command line. Then have fun building strategies even faster and with less RAM than before now and make some money hopefully:)