Realtime regression in 2.6.15-23

[David Meier]

All previous dapper kernels were usable for demanding audio work with the jack soundsystem. With 2.6.15-23 this does not work anymore.

I checked this with -20, -22 and -23 on two systems with different soundcards including a high end card (RME Hammerfall) which I am sure not to be causing the Problem.

With older kernels, jack was perfectly usable even with low latency settings (2.3 msec) and reported maximum scheduling delays of less than a msec. With -23, scheduling delays reaches several hundred msecs, causing corresponding dropouts. This makes the system entirely unusable for audio work even with rather high latency settings of about 20msec. Speedstepping was turned off on all systems. Jack claimed to be running realtime.

I'l be glad to provide more information if requested and help testing patches or config changes.

[Gareth Fitzworthington (mapping-gp-deactivatedaccount)]

This bug has had no activity for a considerable period. This is a check to see if there is still interest in investigating this bug report.

[David Meier (droebbel-melta)]

As there are far better rt-kernels available in newer releases, I have no personal interest in this bug any more. Also, I no longer have access to a hammerfall soundcard and could not do any proper testing. I do not even know if the problem exists with newer dapper kernels or if anyone else can confirm it.
Therefore setting to invalid. Should have closed it long ago, sorry I forgot.