ADAPTIVE_GIANT

From: Manfred Lotz <manfred.lotz(at)arcor.de>
Date: Wed, 30 May 2007 19:46:27 +0200

Hi all,
Ich hätte mal eine Frage zu:

options ADAPTIVE_GIANT # Giant mutex is adaptive.

Dies scheint der Default zu sein. Jedoch steht im Handbuch:

Giant is the name of a mutual exclusion mechanism (a sleep mutex) that
protects a large set of kernel resources. Today, this is an
unacceptable performance bottleneck which is actively being replaced
with locks that protect individual resources. The ADAPTIVE_GIANT
option causes Giant to be included in the set of mutexes adaptively
spun on. That is, when a thread wants to lock the Giant mutex, but it
is already locked by a thread on another CPU, the first thread will
keep running and wait for the lock to be released. Normally, the
thread would instead go back to sleep and wait for its next chance to
run. If you are not sure, leave this in.

Da ich nicht sicher bin, sollte ich die Option also lassen. :-)

Ich würde aber gerne verstehen, ob es vielleicht doch Sinn macht es
weg zulassen. Man könnte aus diesem Text schliessen, dass man ihn
bei einem Ein-Prozessor System nicht (mehr) benötigt.

Kann da jemand was zu sagen?

--
Manfred
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Received on Wed 30 May 2007 - 19:48:45 CEST

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