Re: [LAD] tschack ... early version of smp enabled jack1

From: Patrick Shirkey <pshirkey@email-addr-hidden>
Date: Thu Jan 28 2010 - 04:51:45 EET

>
> sorry about the previous bogus message, i fat-fingered the rewrap
> button... :(
>
> On 01/27/2010 09:11 PM, Stéphane Letz wrote:
>
>> Le 27 janv. 2010 à 21:02, Jörn Nettingsmeier a écrit :
>>
>
>>> i didn't think too much about jack2's apparent overhead, since it
>>> has the benefit of scaling to smp, which usually affects the
>>> single-processor case (my box is a single-core amd64). it would be
>>> interesting to see if torben's approach is able to deliver the same
>>> latencies as jack1, while adding smp support.
>>>
>
>> Well "jack2's apparent overhead," is something new for me, and would
>> require some deeper test/feedback to understand better. Moreover
>> without more precise description of xruns occurrence (at what DSP CPU
>> does it start to happen.. etc..) , what kind of setup (jack2 version,
>> jack configuration, applications used....), it is again hard to
>> understand/correct things.
>>
> well, as i said, it was nothing really conclusive (i'm not going to
> waste much time to go from 128/2 to 64/2, diminishing returns...), and
> my box is generally under-powered for what i do with it.
>
> in short, i figured it's not significant really. i merely added this
> here in case there's a general picture emerging... it wasn't even
> intended as criticism.
>
> and even if it turned out jack2 would be one step worse than jack1,
> that's not at all a big price to pay for smp imho. same with the kernel:
> an smp build does degrade performance on an up box, but who cares,
> really? you can't even buy up workstations any more, and nature dictates
> that single-core performance has hit its limit...
>
>

As a point of reference I just recorded 10 hours of data this past
weekend on my quad core and was having several issues with jackeq +
jack1 prior to starting that were solved by moving to jack2. However I
didn't test with latest svn of jack1 so it may just be the Fedora 12
package of jack1 that was causing me headaches.

Patrick Shirkey
Boost Hardware Ltd

> luck has it that my mobo just got fried, so chances are i'll be
> contributing some nice quad-core data in the near future - if only my
> customers paid their bills on time...
>
>
> best,
>
> jörn
>
> _______________________________________________
> Linux-audio-dev mailing list
> Linux-audio-dev@email-addr-hidden
> http://lists.linuxaudio.org/listinfo/linux-audio-dev
>
_______________________________________________
Linux-audio-dev mailing list
Linux-audio-dev@email-addr-hidden
http://lists.linuxaudio.org/listinfo/linux-audio-dev
Received on Thu Jan 28 08:15:01 2010

This archive was generated by hypermail 2.1.8 : Thu Jan 28 2010 - 08:15:01 EET