Re: A/D converter

Catalin Muresan (cata@codec.ro)
Thu, 22 Apr 1999 13:52:43 +0300


Hello,

On Tue, Apr 20, 1999 at 01:13:40PM -0400, Richard B. Johnson wrote:
root> the speed at which it was expected to interrupt. In fact, the
root> maximum rate at which you can interrupt Linux, and record that an
root> interrupt occurred in your ISR (nothing else), is almost, but not
root> quite, 50 kHz on a dual pentium running 400 MHz with a 100 Mhz main
root> bus. I have a device-driver module which does little more than measure
root> these kinds of things if you are interested.
root>
root> Cheers,
root> Dick Johnson

I understand by this that you could not have, let's say, 60k
interrupts in Linux on a slower machine, which is interesting because we
have two systems here that handle about 60k interrupts/sec on average
(coming from two sources) and the system load is low.

[spot@spot spot]$ grep spot /proc/interrupts ; sleep 1; grep spot /proc/interrupts
7: 24448279 + spot
10: 3015770449 + spot
11: 3146687174 + spot
7: 24448365 + spot
10: 3015811686 + spot
11: 3146726557 + spot
[spot@spot spot]$

3146726557-3146687174=39383 ips
3015811686-3015770449=41237 ips
-------------------------------
80620 ips

CPU Pentium 166 MMX, 32Mb RAM, kernel 2.0.36, MB VIA VPX, 512K cache L2,
66 Mhz bus.

I've tried also with procinfo -D -n1 and there are about 30k
interrupts from each source.

bye,

-- 
 Catalin Muresan                                           CM1206-RIPE
 CODEC Electronic Products                        voice: +40-64-432450
 Internet Services Department                     email: cata@codec.ro
-----------------------------------------------------------------------
  1:33pm  up 12 days, 20:35, 10 users,  load average: 0.10, 0.16, 0.17

- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu Please read the FAQ at http://www.tux.org/lkml/