LPT interruptstorm

Ian FREISLICH if at hetzner.co.za
Mon Aug 2 04:50:17 PDT 2004

"Willem Jan Withagen" wrote:
> Hi,
> Must be a FAQ, but I did not find anything ...
> When wanting to print thru /dev/lpt0 the kernel now starts to complain about
> interruptstorms. Something I can imagine, since printing can generate > 1000
> ints/sec.
> Problem is that the current document (500k) is now printed at 100
> interrupts/sec.
> That's going to take some time....
> How do I prevent this from happening?

/etc/sysctl.conf: hw.intr_storm_threshold=2000


/boot/device.hints: hint.ppc.0.flags="0x8"

Make sure your bios is set to ecp/epp for the printer port, or the
second option will fail.  A couple of people around here have also
suggested 'lptcontrol -e', but every time I've tried that (even
with lpd stopped) I get 'lptcontrol: open: Device busy'.  I'm not
sure what keeps the printer port open other than lpd.


Ian Freislich

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