FAQ Search Today's Posts Mark Forums Read
» Video Reviews

» Linux Archive

Linux-archive is a website aiming to archive linux email lists and to make them easily accessible for linux users/developers.


» Sponsor

» Partners

» Sponsor

Go Back   Linux Archive > 64 Studio > 64 Studio User

 
 
LinkBack Thread Tools
 
Old 06-22-2010, 03:42 PM
"Ralf Mardorf"
 
Default ALSA MIDI latency test - was: opensource.com talk

Title: AW: [64studio-users] ALSA MIDI latency test - was: Re: opensource.com talk







Gustin Johnson wrote:

> On 10-06-21 08:42 AM, Daniel James wrote:

>**

>> Hi Ralf,

>>

>>****

>>>> FAIL

>>>>********

>>>* best latency was 1.29 ms

>>>* worst latency was 7.00 ms, which is too much.

>>>******

>> Thanks for running those tests, that's very helpful.

>>

>> I'd be interested to know if other users can 'pass' this test using our

>> current distros and kernels. If not, it seems like we have some more

>> tweaking to do :-)

>>

>>****

> Those values are what you can expect with USB MIDI.* If you have no

> choice but to use USB gear then try to minimize the number of USB

> devices that are in use.* For example use PS/2 based HIDs (aka keyboard

> and mouse).* Disconnect any other USB devices (such as printers and

> scanners).

>

> Even doing that I do not think that there is much room for improvement.

>

> In the next couple of days I will try and test my own rig with the RME

> and USB MIDI interfaces.*



It's the only USB device in use. Mouse and keyboard are PS/2 devices, my

printer isn't in use, but still a parallel port one and the USB stick is

just for temporarily backups and usually not connected.



I did start a reply regarding to rtirq defaults for USB and I started an experiment, but then my PATA hard disk failed and there is an issue with GRUB for my SATA.



I wasted my whole day with trying to repair GRUB for the SATA, but it didn't work.

Then I tried to run a live cd, to get access to the internet, but there is no new live cd with PPPoE and a lot of old live cds didn't run on my computer or didn't support PPPoE too.



Now I run the Ubuntu 7.10 live cd from a German magazine from 2008, it ships with pppoeconf.



Fazit: At the moment I don't have access to the ALSA MIDI latency packages and I can't run 64 Studio 3.0 beta and 3.3 alpha, both are on the broken PATA.



Tomorrow, perhaps tonight, I'll try to get access to my SATA, resp. to Suse 11.2. I don't have the time to do it now.



Hopefully my PATA will start just one time again, to get it completely up-to-date backuped, at the moment it's disconnected to nurse it.



Anyway, if I shouldn't reply to ALSA MIDI toipics, then it's not because I'm using my Atari ST, but because my PC is broken .





Ralf




_______________________________________________
64studio-users mailing list
64studio-users@lists.64studio.com
http://lists.64studio.com/mailman/listinfo/64studio-users
 
Old 06-23-2010, 09:40 PM
Gustin Johnson
 
Default ALSA MIDI latency test - was: opensource.com talk

On 10-06-22 09:42 AM, Ralf Mardorf wrote:
> Gustin Johnson wrote:
>> On 10-06-21 08:42 AM, Daniel James wrote:
>>
>>> Hi Ralf,
>>>
>>>
>>>>> FAIL
>>>>>
>>>> best latency was 1.29 ms
>>>> worst latency was 7.00 ms, which is too much.
>>>>
>>> Thanks for running those tests, that's very helpful.
>>>
>>> I'd be interested to know if other users can 'pass' this test using our
>>> current distros and kernels. If not, it seems like we have some more
>>> tweaking to do :-)
>>>
>>>
>> Those values are what you can expect with USB MIDI. If you have no
>> choice but to use USB gear then try to minimize the number of USB
>> devices that are in use. For example use PS/2 based HIDs (aka keyboard
>> and mouse). Disconnect any other USB devices (such as printers and
>> scanners).
>>
>> Even doing that I do not think that there is much room for improvement.
>>
>> In the next couple of days I will try and test my own rig with the RME
>> and USB MIDI interfaces.
>
> It's the only USB device in use. Mouse and keyboard are PS/2 devices, my
> printer isn't in use, but still a parallel port one and the USB stick is
> just for temporarily backups and usually not connected.
>
> I did start a reply regarding to rtirq defaults for USB and I started an
> experiment, but then my PATA hard disk failed and there is an issue with
> GRUB for my SATA.
>
The limitations are with how USB actually works. It was not designed
for low latency responsiveness. Messing with IRQs is going to be
enough. You might see some improvement, but not enough to make a
difference.

> I wasted my whole day with trying to repair GRUB for the SATA, but it
> didn't work.
> Then I tried to run a live cd, to get access to the internet, but there
> is no new live cd with PPPoE and a lot of old live cds didn't run on my
> computer or didn't support PPPoE too.
>
If GRUB was installed on the PATA, you will need to install it into your
SATA drive. The difficulty will scale with the number of hard drives
and OSs that you have installed. I know that your system can be
rescued. Most rescue distros have the option to boot an OS off of your
hard drive. The one I use and love is systemrescuecd, though it is very
much CLI orientated.

> Now I run the Ubuntu 7.10 live cd from a German magazine from 2008, it
> ships with pppoeconf.
>
> Fazit: At the moment I don't have access to the ALSA MIDI latency
> packages and I can't run 64 Studio 3.0 beta and 3.3 alpha, both are on
> the broken PATA.
>
> Tomorrow, perhaps tonight, I'll try to get access to my SATA, resp. to
> Suse 11.2. I don't have the time to do it now.
>
> Hopefully my PATA will start just one time again, to get it completely
> up-to-date backuped, at the moment it's disconnected to nurse it.
>
What exactly is wrong with it? If you cannot mount it from a live CD,
then the drive is probably toast.

Hth,

_______________________________________________
64studio-users mailing list
64studio-users@lists.64studio.com
http://lists.64studio.com/mailman/listinfo/64studio-users
 

Thread Tools




All times are GMT. The time now is 06:09 AM.

VBulletin, Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Content Relevant URLs by vBSEO ©2007, Crawlability, Inc.
Copyright 2007 - 2008, www.linux-archive.org