Alternative iconification method

Activation

  (f2::iconify-without-trimming t)

Description

On Windows platforms before Vista, the operating system will trim an application's working set when minimizing it. So when you click an application's "minimize" button, not only will its window disappear, but the operating system will also try to flush out all memory pages to the paging file except for a few pages which are permanently needed by the application even in its idle state. This is also called "working set trimming".

This behavior can be observed by opening the Task Manager and switching to the "Processes" tab. The size of the working set of each process is displayed in the "Mem Usage" column. When you minimize an application, you will notice that a few seconds thereafter, the value in the "Mem Usage" column will decrease sharply (unless the process didn't need a lot of memory pages anyway).

The OS will also try to page out unused pages when an application is idle for a while. The overall strategy makes sense: The OS gives foreground applications priority, both in terms of CPU cycles and physical memory allocation. In most cases, this is what users want.

When minimizing applications which already have allocated many memory pages because they are operating on large data sets (such as CAD applications), however, automatic working set trimming can sometimes be detrimental to performance since paging out the unused pages can take a while, depending on disk and CPU speed, size of the loaded model, OS version, and installed RAM. While paging out or in, the system is not as responsive as usual or feels sluggish.

If you often minimize Creo Elements/Direct Modeling, but do not want the operating system to make space for other applications in RAM, we have developed a utility which intercepts the minimize button and sidesteps the OS working set strategy. Activation is as described above. Minimizing the application window works as before, except that the working set is not automatically trimmed.

Note that this does not prevent the system from paging out memory when it detects that an application has been idle for a while. So if you enable this special trick and minimize the application before you leave in the evening, and then maximize the application window again when you return to work the next morning, the application will still have to page in a lot of memory and therefore feel slow for a little while.

To deactivate the utility, enter

  (f2::iconify-without-trimming nil)

Windows Vista does not trim working sets automatically when minimizing application windows, so this tool is not required on Vista systems.