Date: Sat, 20 Sep 2008 08:44:11 -0700 (PDT) From: kg5nm <kg5nm@comcast.net> To: freebsd-questions@freebsd.org Subject: Re: irq19 uhci interrupts taking ~100% of one core? Message-ID: <19586581.post@talk.nabble.com> In-Reply-To: <a174d0600809072254j1ad277e8jdfb638f7e1b71a11@mail.gmail.com> References: <a174d0600809071607g308a91c0qbc5c114e40c6146e@mail.gmail.com> <a174d0600809072254j1ad277e8jdfb638f7e1b71a11@mail.gmail.com>
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I think this is a SATA driver problem on amd64 builds. I have the same problem (3 usable cores due to this!). I'm too am running a custom kernel but this was also happening on GENERIC. If you temporarily disable all USB drivers, you should see the SATA ATAPI driver pop up on 'vmstat -i' instead of UHCI. IRQ 19 is a multi-use IRQ and vmstat reports one IRQ grabber. An additional clue: I unplugged 3 of my 4 SATA drives and the 'IRQ shower' actually increased about 25%! I'm considering posting this to the -CURRENT folks to see if this is being worked, it's pretty painful to lose 25% of my quad-core just to this interrupt shower; FYI - I'm calling it a 'shower' since it's not bad enough for the kernel to flag it as a storm. :) - Gary (kg5nm@comcast.net) Scott Gasch wrote: > > Replying to my own question with more data. > Previously I had been running my own kernel; I was curious if the problem > would reproduce with a GENERIC kernel. It does but the symptoms are > slightly different. The same irq is firing too often and consuming nearly > all of one core. But the driver that is associated with the interrupt is > different -- it's fwohci0: > > interrupt total rate > irq6: fdc0 1 0 > irq17: mskc0 dc0 313242 13 > irq18: skc0 uhci2* 124475451 5540 > irq19: fwohci0+++ 957875379 42638 > irq23: uhci3 ehci1 1145 0 > cpu0: timer 44458513 1979 > cpu1: timer 44448875 1978 > cpu3: timer 43393901 1931 > cpu2: timer 43393921 1931 > Total 1258360428 56014 > > > This makes me start to wonder if this is not a problem with irq19 (the > PIC?) > and not one particular device / driver. I'm not sure how to make dig > deeper > here, any help greatly appreciated. > > Thx, > Scott > > > On Sun, Sep 7, 2008 at 4:07 PM, Scott Gasch <scott.gasch@gmail.com> wrote: > >> Hi, >> I'm running freebsd 7.0-RELEASE-p4 on a 4-core amd64 box. nearly 100% of >> 1 >> cpu is constantly being used handling irq19: uhci4 interrupts. This >> seems >> to happen both with and without any USB devices plugged in: >> >> vmstat -i >> interrupt total rate >> irq1: atkbd0 5 0 >> irq6: fdc0 1 0 >> irq17: mskc0 dc0 1180547 18 >> irq18: skc0 uhci2* 163250699 2512 >> irq19: uhci4++ 3187989508 49072 >> irq23: uhci3 ehci1 31 0 >> cpu0: timer 129208570 1988 >> cpu1: timer 129208457 1988 >> cpu2: timer 125750147 1935 >> cpu3: timer 125750122 1935 >> Total 3862338087 59452 >> >> dmesg >> uhci4: <UHCI (generic) USB controller> port 0xa400-0xa41f irq 19 at >> device >> 29.1 >> on pci0 >> uhci4: [GIANT-LOCKED] >> uhci4: [ITHREAD] >> >> Any idea what's going on here and/or how to fix this? >> >> Thx, >> Scott >> >> > _______________________________________________ > freebsd-questions@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-questions > To unsubscribe, send any mail to > "freebsd-questions-unsubscribe@freebsd.org" > > -- View this message in context: http://www.nabble.com/irq19-uhci-interrupts-taking-%7E100--of-one-core--tp19363669p19586581.html Sent from the freebsd-questions mailing list archive at Nabble.com.
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