DOCUMENT:Q82228  17-DEC-2000  [win3x]
TITLE   :Use of TimerCriticalSection= in 386 Enhanced Mode Windows
PRODUCT :Microsoft Windows 3.x Retail Product
PROD/VER::3.1
OPER/SYS:
KEYWORDS:

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The information in this article applies to:

 - Microsoft Windows versions 3.0, 3.0a, 3.1, 3.11 
 - Microsoft Windows for Workgroups version 3.1 
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SUMMARY
=======

In the [386Enh] section of the SYSTEM.INI file, the TimerCriticalSection=
setting can be used in Microsoft Windows running in 386 enhanced mode to prevent
system corruption for some networks and terminate-and-stay-resident (TSR)
programs.

MORE INFORMATION
================

The TimerCriticalSection= setting must be entered as follows

      [386Enh]
      TimerCriticalSection=nnnn

where "nnnn" is the amount of time in milliseconds before the critical section is
timed out. For example, a value of 1000 would indicate a 1 second time-out for
the timer critical section.

When this feature is enabled, the virtual machine (VM) assumes ownership of the
critical section before sending a timer interrupt. This prevents timer
interrupts from being serviced in one virtual machine while another virtual
machine is in the critical section (for example, making an MS-DOS call).

The time-out feature allows you to fine-tune the amount of time Windows blocks a
timer interrupt from being serviced in a virtual machine. When a virtual machine
returns from servicing a timer interrupt, the critical section is released and
the time-out is canceled to allow other virtual machines to service timer
interrupts. Typically the time-out will never occur, so it is best to set the
TimerCriticalSection= value to a large value such as 5000. A virtual machine
would then be allowed to "own" all timer interrupts for up to 5 seconds before
other virtual machines would be allowed to run. Because timer interrupt service
routines return very quickly in almost all situations, this will not present a
problem. However, a pop-up program such as Borland's SideKick pops-up on a timer
interrupt and does not return until you pop it down. The time-out is provided to
handle this situation.

TimerCriticalSection=2000 has prevented system corruption on both Banyan and
Novell networks.

Additional query words: 3.0 3.0a 3.1 3.00 3.00A 3.10 3.11

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Keywords          :  
Technology        : kbAudDeveloper kbWin3xSearch kbWFWSearch kbZNotKeyword3 kbWin300 kbWin300a kbWin310 kbWin311 kbWFW310
Version           : :3.1

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