Re: [Jack-Devel] Call for testing of MIDI Drivers in JACK 2

On Thu, Apr 7, 2011 at 11:42 PM, Devin Anderson
<[hidden]> wrote:
> On Thu, Apr 7, 2011 at 10:42 PM, Clemens Ladisch <[hidden]> wrote:
>> BTW: jackd seems to have some problems opening the ports of the
>> snd-virmidi driver, but the test works.
>
> I wasn't aware of the 'snd-virmidi' driver.  I'll take a look when I
> get a chance.

There's a problem with JACK MIDI port name uniqueness in the
'alsarawmidi' driver.  I've committed a fix to the GIT repo, but it
isn't available in JACK 2 SVN yet.

When I run JACK 2 with the fix, I see 4 virtual raw MIDI devices, each
with 16 input ports and 16 output ports.  It appears that the increase
in the port count produces more jitter in the driver, I assume because
of the polling of 128 file descriptors, but I'm not totally sure.

I wonder if using the 'epoll' interface instead of 'ppoll' would be faster.

-- 
Devin Anderson
devin (at) charityfinders (dot) com

CharityFinders - http://www.charityfinders.com/
synthclone - http://synthclone.googlecode.com/

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