[IPython-User] failed to respond to heartbeat

Matthias BUSSONNIER bussonniermatthias@gmail....
Tue Jan 29 10:36:13 CST 2013

Le 29 janv. 2013 à 17:24, Jeremy Harbinson a écrit :

> Hi,
> I am using the IPython Notebook on Mac OS X v 10.8.2 using the Enthought Python distribution (7.3) (according to Enthought site the IPython version 0.13.1, but I have been unable to check this  for my installation) and with Firefox as the browser. The computer is a late 2012 version MacBook Pro.
> When awaking the computer from Sleep or Deep Sleep ( I guess these are hibernate modes 3 and 1 respectively) I get often get an error message from the notebook that the kernel has 'failed to respond to heartbeat' and I need to restart it. I had a look on the internet and there are some suggestions that could be fixed by increasing the setting for 'MultiKernelManager.time_to_dead', but generally not explaining it very clearly, though this is more down to me rather than the author, I guess. Is the Multimanager etc fix the best one to use (if it is could you explain how best to apply it?)  or is there a better option?

*KernelManager ping the kernel process[1] every now and then through ZMQ to be sure they respond, if they don't respond they assume the process is dead and ask you to restart it. 
the MultiKernelManager is just the KernelManager of the notebook. 

to change it you just have to add 
c.MultiKernelManager.time_to_dead=a_number  (in seconds I guess)
In your notebook_profile (~/.ipython/profile_xxx/ipython_notebook_config.py )

Still I don't know how this behave in deep sleep how the delta-time to dead is computed and you might have to set this number to higher than the time of sleep, I'm not the expert on this part of the code.

I don't know of the best fix, I guess we could try to monitor time between ping sending and allow a grace period if we see that no ping have been sent for more that 5 min or something like that. 
Not even sure it is possible.


[1] actually a nanny process of the kernel process IIRC

> all the best,
> Jeremy
> _______________________________________________
> IPython-User mailing list
> IPython-User@scipy.org
> http://mail.scipy.org/mailman/listinfo/ipython-user

More information about the IPython-User mailing list