Re: [announce] [patch] limiting IRQ load, irq-rewrite-2.4.11-B5

Tim Hockin
2001-10-01T22:45:29Z

> - a little utility written by Simon Kirby proved that no matter how much
> softirq throttling, it's easy to lock up a pretty powerful Linux
> box via a high rate of network interrupts, from relatively low-powered
> clients as well. 2.4.6, 2.4.7, 2.4.10 all lock up. Alexey said it as
> well that it's still easy to lock up low-powered Linux routers via more
> or less normal traffic.

We proved this a year+ ago. We've got some code brewing to do fair sharing
of IRQs for heavy load situations. I don't have all the details, but
eventually...

> i've tested the patch on both UP, SMP, XT-PIC and APIC systems, it
> correctly limits network interrupt rates (and other device interrupt
> rates) to the given limit. I've done stress-testing as well. The patch is
> against 2.4.11-pre1, but it applies just fine to the -ac tree as well.

Our solution/needs are slightly different - we want to service as many
interrupts as possible and do as much network traffic as possible, and
interactive-tasks be damned.