[AG-TECH] Dropping OSS device in Rat (Linux)

[Jason Bell]

G'day Ben

The issue that I mentioned is in regards to OSS, you shouldn't see the
problem with ALSA.  

I am surprised that you are using ALSA, as the audio quality is
significantly better using OSS.

I have never experienced the issue of the device not being present
straight away (which should always be the case).  But I am pretty sure
there are no special scripts or anything like that which would delay you
from seeing the device.  With the newer versions of Linux (using the
newer kernels), the video devices can actually be shared, unlike the OSS
device, therefore there would be no reason to do any delaying, etc.

Cheers,
Jason.


-----Original Message-----
From: Ben Green [mailto:Ben.Green at manchester.ac.uk] 
Sent: Wednesday, 31 October 2007 8:55 PM
To: Jason Bell; ag-tech; accessgrid-l at clix.aarnet.edu.au
Subject: RE: [AG-TECH] Dropping OSS device in Rat (Linux)

Hi Jason,

I don't get this issue luckily, my OSS device is always there alongside
the ALSA one. I use the ALSA as default. I'm running FC7.

But I do see a similar issue when starting the video producer service,
and it can take 10 seconds for it to recognise my video device (I just
get a blank in the drop down device menu). I'm sure other people have
seen this too.

I would image getting vic to sleep for 10 seconds before starting would
resolve this, in a similar way to how your shell script makes rat wait a
bit longer before starting (I assume that's what it's doing).

Cheers, Ben.

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-----Original Message-----
From: owner-ag-tech at mcs.anl.gov [mailto:owner-ag-tech at mcs.anl.gov] On
Behalf Of Jason Bell
Sent: 31 October 2007 05:56
To: ag-tech; accessgrid-l at clix.aarnet.edu.au
Subject: [AG-TECH] Dropping OSS device in Rat (Linux)

G'day all

This is just a quick email to see if anyone else has been experiencing
an issue that I have been having lately.

Basically on my "Linux" systems (Fedora Core 6 and Fedora 7), sometimes
when Rat is started, the Device "OSS" device is missing in which is then
defaulted to an "ALSA" device.

The reason why this is an issue is the "OSS" device produces far
superior audio quality, when compared to "ALSA" (Though I realize that
"OSS" is just a wrapper on ASLA with the default Fedora Kernel).

>From my understanding, the reason why this occurs is that, if the OSS
device is in use, it then becomes unavailable and no longer displayed as
a device, as OSS only allows one application exclusive access.

Anyway, from doing some basic testing, it was seen that events like
switching from one venue to another was causing this to happen.  It
appeared that if the machine was heavily loaded, this would increase the
chance of this happening.

Anyway, to cut a long story short, I deleted the /usr/bin/rat sym link
and replaced it with a basic shell script:

	#! /bin/sh

	sleep 5
	exec /usr/bin/rat-4.4.00 "$@"

>From some initial testing, it appears to have fixed the issue!  (More
testing is required)

I'm just wondering if anyone else has experienced this issue with Fedora
or other Linux systems???

Thanks for your time,
Jason.


--------------------------------------------
Jason Bell, B.I.T.

B. Info. Tech. (Honours) Student

High Performance Computing Support Officer,
Network Engineer
Information Technology Division
Central Queensland University

E-mail : j.bell at cqu.edu.au
Phone : 07 4930 9229
--------------------------------------------
Patience is a virtue.

But if I wanted Patience,
I would have become a Doctor.
--------------------------------------------