[LAU] midi triggering delay

[andy baxter]

hollunder at gmx.at wrote:
> On Tue, 08 Sep 2009 14:48:27 +0100
> andy baxter <andy at earthsong.free-online.co.uk> wrote:
>
>   
>> James Cameron wrote:
>>     
>>> On Tue, Sep 08, 2009 at 10:14:24AM +0100, andy baxter wrote:
>>>   
>>>       
>>>> - using a program which turns the computer keyboard into a virtual
>>>> midi device. This makes the sound much more immediate. Having
>>>> tried this, the contrast makes it obvious that there is still a
>>>> problem with delays from the edirol keyboard.
>>>>     
>>>>         
>>> ...
>>>
>>> Watch /proc/interrupts while trying to play, and see what counters
>>> increment in the matrix.  Here's a fun way ... run this in a
>>> terminal window while playing keys on the MIDI keyboard ...
>>>
>>> 	watch -d --interval=0.1 cat /proc/interrupts
>>>
>>> What is the kernel version?  You mentioned Debian Testing and Ubuntu
>>> Jaunty.
>>>   
>>>       
>> I'm using a hand compiled kernel under debian testing - 2.6.26.8 with 
>> the rt16 patch. I also tried a 2.6.29 kernel with rt23, but this
>> didn't work. (May have been my mistake but I ended up with a problem
>> with repeating keys and also the jack daemon wouldn't start properly.)
>>
>> Will try what you've suggested and let you know how it goes.
>>
>> Many thanks for the time you've spent looking into this.
>>
>> cheers,
>>
>> andy
>>     
>
> He, so I was not the only one who got the repeating key problems with
> 2.6.29-rt. I think I had other issues as well.
> Now if only 2.6.31-rt was out already :)
>
>   
I also had a problem with the xserver crashing and behaving oddly with 
the intel driver, which was only curable by switching to the vesa driver.
> I use a keyboard with midi over usb and the output is over a usb
> interface, yet I haven't noticed any annoying delay. At the moment jack
> is set to 16ms, which of course is more when you measure it, especially
> with usb.
>   
What distro and kernel are you using? If all else fails I'll maybe copy 
your setup.

andy