On 30.12.2003, at 19:57, Dirk-Willem van Gulik wrote:
> First I hear of that - and would be interested in digging into it. Any
> pointers to a description ?
Basically, it seems that when pushing data at maximum speed (Ethernet
-> Ethernet) through a net45xx that runs FreeBSD (m0n0wall actually),
the CPU gets so fed up with handling all the interrupts (and packet
filtering/NAT too) that the watchdogd process doesn't get any CPU time
to tickle the watchdog anymore. Raising the priority of the process
doesn't help either.
> I've used it both in wirelessleiden.nl and in commercial project and
> observed this; nor with 100Mbit ether or WiFi. Are we sure this is not
> artifact of polling mode and a HZ setting introduced at the same time ?
Au contraire - polling mode actually "solved" the problem by leaving
watchdogd enough CPU time even at max. throughput.
> No trouble. Whichever is easiest; though given the way this code works
> given the way the HW of the Elan works - I seriously do dount that the
> watchdog is the cause - perhaps more a sympthom; a few cycles userland
Well, the watchdog and your watchdog daemon work as expected -
resetting the box when it is "hung" (no more userland activity ;).