Date: Thu, 22 Apr 2004 09:13:02 -0400 From: John Baldwin <jhb@FreeBSD.org> To: freebsd-hardware@freebsd.org Cc: Artem Koutchine <matrix@itlegion.ru> Subject: Re: ACPI floods CPUs with interrupts Message-ID: <200404220913.02440.jhb@FreeBSD.org> In-Reply-To: <010501c426db$cc281a10$0c00a8c0@artem> References: <010501c426db$cc281a10$0c00a8c0@artem>
next in thread | previous in thread | raw e-mail | index | archive | help
On Tuesday 20 April 2004 09:31 am, Artem Koutchine wrote: > I have installed FreeBSd 5.2-RC2 on ASUS P2B-DS > with 3ware raid controller and DUAL PIII (slot2) 550Mhz. > Updated motherboard bios to > the latest bios and after patching the twe driver, so it does not > show the "PCI parity erro" several times a second. (I think > it is related to the fact that 3ware 7506 controller is pci 2.2 > while p2b is pci 2.1). After that i did top and saw that > 50% of cpu power is wasted on interrupts. I did > sysstat and :vmstat. It showed that 46700 interrupts per > second were generated by acpi on irq 20. So, i booted without > acpi and got 100% cpu idle. The question is: > How ACPI can generate IRQs? I thought it is just some kind > of interface and protocol standard, not > a real hardware part which > can rise irq. Why does it generate so many irqs? May it be related > to the PCI parity error on twe? It is because the ACPI interrupt is programmed incorrectly (due to a buggy BIOS) and is treated as edge triggered when it is actually level triggered. You can try updating to -current to see if that fixes it. -- John Baldwin <jhb@FreeBSD.org> <>< http://www.FreeBSD.org/~jhb/ "Power Users Use the Power to Serve" = http://www.FreeBSD.org
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200404220913.02440.jhb>