lpt0 printer slows system response significantly

[Anton Shterenlikht]

On Fri, Nov 03, 2006 at 03:03:21AM +1100, Ian Smith wrote:
> On Wed, 1 Nov 2006 Anton Shterenlikht wrote:
>  > On Wed, Nov 01, 2006 at 10:49:36AM -0500, Lowell Gilbert wrote:
>  > >  * Change the printer port to polled mode.  ["lptcontrol -p"]
>  > >    With this kind of hardware, it may even speed up your printing as well.
>  > 	Thanks a lot, I think it does print a bit faster. But more
>  > importantly I see virtually no performance degradation during
>  > printing.
>  > 
>  > 	On slower machines using interrupt mode might cause
>  > 	significant degradation of the overall system perfor-
>  > 	mance due to the interrupt service using most of the
>  > 	CPU time. On such machines changing to polled mode
>  > 	will balance the CPU load as well as result in
>  > 	faster printing.
>  > 
> 
> I'm not sure if that's generally true for slower machines; you haven't
> said (or I missed) what sort of printer you're using, what filters you
> run via printcap, and such?  Not one covered by the existing para?
> 
> I have a 1500c, bit faster than your 1700 @300MHz, that has printed lots
> of large files via gs without ever seeing any significant irq 7 load nor
> any slowdown of the machine at all - albeit using a slow old printer. 
> 
> Not that I see any problem with your proposed addition.  Perhaps 'On
> some slower machines running fast printers using interrupt mode ..' ? 
> 
> Cheers, Ian

That's interesting.
I use lj2100 with apsfilter via printcap.

aps1|lp|laserjet;r=1200x1200;q=medium;c=gray;p=a4;m=auto:\
    :lp=/dev/lpt0:\
    :if=/usr/local/etc/apsfilter/basedir/bin/apsfilter:\

thanks
anton