interesting(?) data on network interrupt servicing

[Poul-Henning Kamp]

In message <20060322122906.A41691 at xorpc.icir.org>, Luigi Rizzo writes:

>    if (thread)
>	isrc->is_pic->pic_disable_source(isrc, PIC_EOI);
>
>I have no idea, though, why the other pic_disable_source()
>is so expensive. The 4-5k TSC ticks are approx 3us
>
>Any clues ?

ISA bus access.

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Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
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