Moving Playhead increases DSP load up to 90%

[lilith93]

I currently have a project with an average RT DSP load of ~10%. When moving the playhead (i.e. jumping to another position) however the DSP load peaks at ~95% sometimes. That caused basically xruns and short clicks everytime I moved the playhead. This only happnes when using Jack, with Alsa everyting is fine.

When I move the playhead during the track is playing the increase in DSP load is very little when moving the playhead. It's much worse when the transport is stopped.

Now I activated the option "Server synchronous mode" in Jack and the xruns are gone!

I opened a similar thread some time ago:
https://forum.cockos.com/showthread.php?t=222259

Let's see if this also affects the pulse audio issue.

Does anyone have an explanation for that behaviour and also why there's this huge DSP load when "just" moving the playhead?

[lilith93]

Activating Server Synchronous Mode doesn't seem to be a good option as Reaper frequently crashes. In the log window of jack there are these errors:

Sun May 17 02:18:54 2020: ERROR: JackFreewheelDriver::ProcessSync: SuspendRefNum error
Sun May 17 02:18:54 2020: ERROR: JackAudioDriver::ProcessGraphSync: ProcessWriteSlaves error, engine may now behave abnormally!!
Sun May 17 02:18:54 2020: ERROR: JackPosixProcessSync::LockedTimedWait error usec = 5000000 err = Connection timed out
Sun May 17 02:18:54 2020: ERROR: JackEngine::ClientDeactivate wait error ref = 6 name = REAPER
Sun May 17 02:18:54 2020: ERROR: JackEngine::ClientKill ref = 6 cannot be removed from the graph !!
Sun May 17 02:18:54 2020: ERROR: Failed to find port 'REAPER:MIDI Input 1' to destroy
Sun May 17 02:18:54 2020: ERROR: Failed to find port 'REAPER:MIDI Input 2' to destroy
Sun May 17 02:18:54 2020: ERROR: Failed to find port 'REAPER:in1' to destroy
Sun May 17 02:18:54 2020: ERROR: Failed to find port 'REAPER:in2' to destroy
Sun May 17 02:18:54 2020: ERROR: Failed to find port 'REAPERut1' to destroy
Sun May 17 02:18:54 2020: ERROR: Failed to find port 'REAPERut2' to destroy
Sun May 17 02:18:55 2020: ERROR: JackPosixProcessSync::LockedTimedWait error usec = 1000000 err = Connection timed out
Sun May 17 02:18:55 2020: ERROR: JackEngine::ClientCloseAux wait error ref = 6
Sun May 17 02:18:55 2020: Client 'REAPER' with PID 8693 is out
Sun May 17 02:18:59 2020: ERROR: JackAudioDriver::ProcessGraphSync: SuspendRefNum error, engine may now behave abnormally!!

[lilith93]

This seems to be fixed in the latest version 😁