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From: John Baldwin <jhb@freebsd.org>
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Date: Tue, 28 Aug 2012 07:44:23 -0400
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	(bigwig.baldwin.cx); Tue, 28 Aug 2012 07:45:44 -0400 (EDT)
Cc: freebsd-current@freebsd.org
Subject: Re: What is "Fast task queue"? (Was: How to understand what `swi5'
	kernel thread does?)
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On Monday, August 27, 2012 4:47:13 pm Lev Serebryakov wrote:
> Hello, John.
> You wrote 27 =D0=B0=D0=B2=D0=B3=D1=83=D1=81=D1=82=D0=B0 2012 =D0=B3., 20:=
26:03:
>=20
> >>  What "fast tasks" are performed via this queue? Under network load it
> >> is main consumer of CPU.
> JB> Certain NIC drivers perform much of their interrupt handling in that=
=20
thread.
>   Yep,  I've found, that my if_vr uses it. One more question: does ipfw
>  rules works in same thread? I have ``net.isr.dispatch=3D"direct"'' set.

Yes, with the default setting of direct dispatch, all of the receive
side of the network stack runs in the driver's interrupt handler.  In
the case of vr(4) that would be in this thread.

=2D-=20
John Baldwin