Re: [PATCH] 2.4.1-ac UP-APIC updates

Ingo Molnar (mingo@redhat.com)
Tue, 20 Feb 2001 13:46:18 -0500 (EST)


On Tue, 20 Feb 2001, Mikael Pettersson wrote:

> * NMI rate reduction for UP-APIC: the 100Hz default rate is excessive for
> normal systems, 1Hz suffices. It turns out we cannot start at 1Hz due to
> this interacting badly with check_nmi_watchdog() and the watchdog itself,
> so the rate is reduced after check_nmi_watchdog() is done.

i dont like this one. 100 times a second makes absolutely no performance
difference whatsoever - but eg. i'm driving kernel profiling from the NMI
handler to get profiles of eg. IRQ handlers and other cli()-ed code areas.

another reason is that if NMIs intaract with anything else in the system,
we'll have much better chances to hit it with 100 Hz than with 1 Hz.

Ingo

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