Re: [LAU] midi triggering delay

andy baxter wrote:
> James Cameron wrote:
>> On Tue, Sep 08, 2009 at 07:17:30PM -1000, david wrote:
>>
>>> USB not sharing interrupts with anything?
>>>
>>
>> Andy's original post contained /proc/interrupts which showed some
>> sharing was happening. Here's a cut:
>>
>> 16: 380396 233180 IO-APIC-fasteoi uhci_hcd:usb4, yenta
>> 17: 829711 532117 IO-APIC-fasteoi uhci_hcd:usb5,
>> ohci1394, HDA Intel
>> 18: 0 0 IO-APIC-fasteoi mmc0
>> 19: 2 0 IO-APIC-fasteoi ehci_hcd:usb6
>> 20: 18 17 IO-APIC-fasteoi uhci_hcd:usb1
>> 21: 0 0 IO-APIC-fasteoi uhci_hcd:usb2
>> 22: 305246 302929 IO-APIC-fasteoi ehci_hcd:usb3
>>
>> Sharing interrupts adds a tiny delay to interrupt handling; if this has
>> truly become significant, there's a design issue somewhere else.
>>
>> (Shared interrupts with modern kernels are not a huge problem, since the
>> drivers check to see if the interrupt they have is legitimate before the
>> kernel chains on to the next driver. It's the waste of that additional
>> check that people want to avoid.)
>>
> The usb port I'm using is on INT 21 (uhci_hcd:usb2), which doesn't share
> with anything.

Hmmm. Which video driver are you using (maybe you already mentioned it)?
If using Intel, try VESA, or viceversa, just in case it's the video
driver doing something?

-- 
David
gnome@email-addr-hidden
authenticity, honesty, community
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