Re: help w/ mutex

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From: Slava M. Usov (stripit.slough_at_gmx.net)
Date: 05/05/04 

Date: Wed, 5 May 2004 22:51:04 +0200

"Gary Chanson" <gchanson@No.Spam.TheWorld.net> wrote in message
news:eOIZmStMEHA.740@TK2MSFTNGP12.phx.gbl...

[...]

> Another reason to not use a semaphore in place of a mutex is the
> priority inversion problem. A semaphore can block a high priority thread
> while a lower priority thread executes, effectively lowering the priority
> of the high priority thread to that of the lower priority thread. Mutexes
> deal with this problem by temporarily raising the priority of the low
> priority thread to that of the higher priority thread while it is blocked.

Huh? Certainly not in win32. In win32, priority inversion is dealt with by
random thread boosting -- which stops working as you go into the real-time
class.

S

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