Hi,
i use Ubuntu and in the last days, i was already running pd succesfully together with Jack. Now, everytimes when i tell pd to use Jack by clicking on it in the option menu and confirming the dialog, the terminal gives following output:

Cannot lock down 82274202 byte memory area (Cannot allocate memory)
watchdog: signaling pd...
watchdog: signaling pd...
watchdog: signaling pd...

The last statement keeps printing itself again and again.
Meanwhile the pd gui does not react on any input anymore.
Do you know this problem?

Since there is still no answer, maybe the jack output will help. This output appears at the same time, when pd starts its output from my previous posting, and keeps repeating itself.
Might that be some kind of dead lock/ live lock ?

 JackPosixSemaphore::TimedWait err = Connection timed out
JackFreewheelDriver::ProcessSync: SuspendRefNum error
JackAudioDriver::ProcessGraphSync: ProcessWriteSlaves error, engine may now behave abnormally!!
JackPosixSemaphore::TimedWait err = Connection timed out
JackFreewheelDriver::ProcessSync: SuspendRefNum error
JackAudioDriver::ProcessGraphSync: ProcessWriteSlaves error, engine may now behave abnormally!!
JackPosixSemaphore::TimedWait err = Connection timed out
JackAudioDriver::ProcessGraphSync: SuspendRefNum error, engine may now behave abnormally!!
JackPosixSemaphore::TimedWait err = Connection timed out
JackFreewheelDriver::ProcessSync: SuspendRefNum error
JackAudioDriver::ProcessGraphSync: ProcessWriteSlaves error, engine may now behave abnormally!!
JackPosixSemaphore::TimedWait err = Connection timed out
JackAudioDriver::ProcessGraphSync: SuspendRefNum error, engine may now behave abnormally!!

I have had this problem as well. a circumvent it by flagging -jack in initialization arguments. hope it helps!

Thanks a lot, it helped. Although if i restart jack, i need to restart pd as well or else it will result in the same problem.