Re: Lossy interrupts on x86_64

From: Chris Snook
Date: Thu Sep 13 2007 - 09:41:27 EST


Jesse Barnes wrote:
I just narrowed down a weird problem where I was losing more than 50% of my vblank interrupts to what seems to be the hires timers patch. Stock 2.6.23-rc5 works fine, but the latest (171) kernel from rawhide drops most of my interrupts unless I also have another interrupt source running (e.g. if I hold down a key or move the mouse I get the expected number of vblank interrupts, otherwise I get between 3 and 30 instead of the expected 60 per second).

Any ideas? It seems like it might be bad APIC programming, but I haven't gone through those mods to look for suspects...

What happens if you boot with 'noapic' or 'pci=nomsi'? Please post dmesg as well so we can see how the kernel is initializing the relevant hardware.

-- Chris
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