RtcplSetStarvationTimeout

The function RtcplSetStarvationTimeout sets the Starvation timeout interval.

Syntax

BOOL RtcplSetStarvationTimeout(
    DWORD Behavior,
    DWORD Timeout
);

Parameters

Behavior

One of the following defines:

Value	Description
STARVATION_YIELD	RTX performs a context switch from RTSS to Windows for the remaining time of the current tick.
STARVATION_FREEZE	RTX stops or freezes all RTSS applications, depending on the process exception disposition setting, which you can obtain with RtcplGetFreezeFaultingProcessOnException.
STARVATION_DISABLE	The starvation timer is disabled and so RTX does not monitor for Windows starvation.

Timeout

Specifies the number of microseconds of the starvation time out period. This parameter is ignored if Behavior is set to STARVATION_DISABLE. The minimum value can not be less then the Hal Timer Period, unless disabling the timeout by setting the value to 0. The minimum (and default) value is 0 and the maximum is 10,000,000.

Return Values

A non-zero value if the function succeeds

Remarks

Changing this behavior requires a restart of the RTX Subsystem if it is running, as indicated by a GetLastError of ERROR_SUCCESS_RESTART_REQUIRED.

You can make the RTX Scheduler monitor for highly CPU-intensive RTSS applications and notify the RTX subsystem if Windows has not been allowed to run for a period of time that you specify. The timeout value for Windows starvation depends on RTX load, Windows application load, and whether or not your application uses multimedia timers.

You can configure how RTX treats these Windows starvation notifications:

When notifications are treated as starvation exceptions, all RTSS applications are stopped or frozen.
When the notifications are treated as requests to yield to Windows, the RTX scheduler performs a context switch from RTSS to Windows for the remaining time of the current tick, possibly delaying an RTSS thread for up to one HAL timer period. This could affect some RTSS applications or drivers if there is a real time interrupt or timer being serviced at a very high rate (>10 KHz) and this latency is a significant fraction of the time between events. If this is the case, increase the starvation timeout value until the expected behavior is achieved.

Related RTX Properties Control Panel Features

Tab	Starvation tab
Feature(s)	Starvation options

Requirements

Header	RtxProp.h
Library	RtxProp.lib

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