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AR# 1894

5.2.1 PPR - Execution on PC is slow on Windows 3.11



Urgency: standard

General Description:

Customers sometimes complain their PC is running the XACT tools very slow. There are cases when 486s at 66mhz runs PPR faster than a Pentium running at 200mhz.

The problem may be caused because windows 3.11 is not allocating enough time slices to background processes. For example, when running ppr from the flow engine, the foreground process will be the Flow Engine which is visible to the user, while the background process will be PPR. The current settings for time scheduling on windows 3.11 may not be optimum for the xact tools.
Many times, either be default or set by the user, Windows 3.11 allocates many more slices to the foreground processes than the background processes.

Therefore, it would make sense to allocate more time slices to PPR than the flow engine which is static for most of the time.

In order to see how the foreground and background time slices are distributed do the following:

1. On Windows, open the MAIN folder
2. Double Click on the ENHANCED 386 icon.
3. Then ENHANCED GUI pops out. Take a look at the two numbers corresponding to Windows in Foreground and Windows in Background.

If the ratio between the slices on Windows in Foreground and Windows in Background is much greater than 2 then PPR will be very slow as well as all the other DOS tools called from the Windows GUIs.


Change Windows in Foregound to 50 and Windows in Background to 50 or greater (Don't push this number too high because all your windows applications will become very slow)
AR# 1894
Date 03/22/2000
Status Archive
Type ??????