Interrupt latency problems

[Robert Watson]

On 10 May 2003, Paul Richards wrote:

> Is everyone seeing this? If not then perhaps we can narrow down the
> problem and look at getting things improved before 5-stable, because if
> it stays like this it's not really what I'd consider useable. 

If you look at the 5.2-RELEASE feature requirements, you'll see that they
include fine-grained locking for ATA to mitigate this problem.  I know
there's work-in-progress to look at issues relating to CAM and the various
storage drivers as well.  You can take a look at the driver status page to
see the status of various hardware drivers --

  http://www.FreeBSD.org/projects/busdma/

I believe.  It's grown from "do drivers handle busdma" to "which drivers
are MPsafe to various degrees, 64-bit safe, etc".

Robert N M Watson             FreeBSD Core Team, TrustedBSD Projects
robert at fledge.watson.org      Network Associates Laboratories