This value determines how long the port thread waits before giving up, pausing the current print job, and moving to the next print job.

Hive: HKEY_LOCAL_MACHINE
Key: SYSTEM\CurrentControlSet\Control\Print
Name: FastPrintWaitTimeout
Type: REG_DWORD
Value: 24,000 msecs default 4mins

FastPrintThrottleTimeout type REG_DWORD Range: Milliseconds, Default: 2,000 (2 seconds) When JobPrintsWhilstSpooling is enabled, some printers pause if they don't receive data for a timeout period (usually 15 seconds for a Postscript printer). To counteract this, the spooler throttles back on data sent to the printer when FastPrintSlowDownThreshold is reached. At that point, FastPrintThrottleTimeout causes 1 byte per defined period to be sent to the printer until the threshold defined by FastPrintSlowDownTheshold is exceeded.

FastPrintSlowDownThreshold type REG_DWORD Range: Milliseconds, Default: FastPrintWaitTimeout divided by FastPrintThrottleTimeout

NetPrinterDecayPeriod type REG_DWORD Range: Milliseconds, Default: 3,600,000 (1 hour) Specifies how long to cache a network printer. The cache is used to present the list of printers to the browser.

PortThreadPriority type REG_DWORD Default: 0 Allows you to set the priority of the port threads. These are the threads that send the output to the printers. Valid values are:
0 (Normal)
1 (Above normal)
0xFFFFFFFF (Below normal)

SchedulerThreadPriority type REG_DWORD Default: 0 The priority of a thread determines the order in which it is scheduled to run on the processor. Valid values are:
0 (Normal)
1 (Above normal)
0xFFFFFFFF (Below normal)

SpoolerPriority type REG_DWORD Default: 0 Sets the priority class for the print spooler. Valid values are:
0 (Normal)
1 (Above normal)
0xFFFFFFFF (Below normal)

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