Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

KernelManagers don't use zmq eventloop properly #967

Closed
minrk opened this issue Nov 2, 2011 · 2 comments
Closed

KernelManagers don't use zmq eventloop properly #967

minrk opened this issue Nov 2, 2011 · 2 comments
Milestone
0.12

Comments

@minrk
Copy link
Member

minrk commented Nov 2, 2011

The KernelManagers use sockets and tornado handlers directly via add/drop_io_state, thus essentially duplicating the ZMQStream objects that handle the state triggering, queuing, etc. already. Approximately all of the private methods on these channels are redundant with code already in ZMQStream.

Also, each channel should probably not be in a separate thread, they should share one ioloop instance between them, and it should be possible for this loop to be run in the main thread if so desired. The most apparent problem this causes (a minor one) is that stopping the channels can take a full second if there is no traffic on the network, which is a long time. I cannot think of any benefit to the channels running in their own threads, as they do now.

This is a low-ish priority, because the code we have works, but it should definitely be fixed.
@minrk
Copy link
Member Author

minrk commented Nov 3, 2011

I should also note that the polling logic in the HB channel is unnecessarily complicated, and actually wrong in some places. There is a comment interpreting poll() returning an empty list as a zeromq bug, which it certainly is not, and the code appears to follow this misunderstanding. Since this bug is actually critical to getting the terminal-frontend working, I will at least fix that part over in #864.

minrk added a commit that referenced this issue Nov 3, 2011
@minrk
Fixes to the heartbeat channel
f9de65b 
* The heartbeat channel had some erroneous zeromq logic, and entirely False comments (as described in #967).  This has been fixed.

* KernelManager.is_alive() checks if the hb_channel is running if
the kernel is not owned, rather than always returning True.

* BlockingKM's hb_channel has been relaxed to 1s polling, because replies are not
reliably much faster than that.  There are occasional >0.5s outlier responses.
minrk added a commit that referenced this issue Nov 7, 2011
@minrk
Fixes to the heartbeat channel
ac70da8 
* The heartbeat channel had some erroneous zeromq logic, and entirely False comments (as described in #967).  This has been fixed.

* KernelManager.is_alive() checks if the hb_channel is running if
the kernel is not owned, rather than always returning True.

* BlockingKM's hb_channel has been relaxed to 1s polling, because replies are not
reliably much faster than that.  There are occasional >0.5s outlier responses.
minrk added a commit that referenced this issue Nov 21, 2011
@minrk
Fixes to the heartbeat channel
649aa17 
* The heartbeat channel had some erroneous zeromq logic, and entirely False comments (as described in #967).  This has been fixed.

* KernelManager.is_alive() checks if the hb_channel is running if
the kernel is not owned, rather than always returning True.

* BlockingKM's hb_channel has been relaxed to 1s polling, because replies are not
reliably much faster than that.  There are occasional >0.5s outlier responses.
@minrk
Copy link
Member Author

minrk commented Nov 27, 2011

closed by PR #1030

@minrk minrk closed this as completed Nov 27, 2011
minrk added a commit that referenced this issue Nov 29, 2011
@minrk
Fixes to the heartbeat channel
804dd6f 
* The heartbeat channel had some erroneous zeromq logic, and entirely False comments (as described in #967).  This has been fixed.

* KernelManager.is_alive() checks if the hb_channel is running if
the kernel is not owned, rather than always returning True.

* BlockingKM's hb_channel has been relaxed to 1s polling, because replies are not
reliably much faster than that.  There are occasional >0.5s outlier responses.
minrk added a commit that referenced this issue Dec 6, 2011
@minrk
Fixes to the heartbeat channel
f7e44e6 
* The heartbeat channel had some erroneous zeromq logic, and entirely False comments (as described in #967).  This has been fixed.

* KernelManager.is_alive() checks if the hb_channel is running if
the kernel is not owned, rather than always returning True.

* BlockingKM's hb_channel has been relaxed to 1s polling, because replies are not
reliably much faster than that.  There are occasional >0.5s outlier responses.
mattvonrocketstein pushed a commit to mattvonrocketstein/ipython that referenced this issue Nov 3, 2014
@minrk
Fixes to the heartbeat channel
7d56d1a 
* The heartbeat channel had some erroneous zeromq logic, and entirely False comments (as described in ipython#967).  This has been fixed.

* KernelManager.is_alive() checks if the hb_channel is running if
the kernel is not owned, rather than always returning True.

* BlockingKM's hb_channel has been relaxed to 1s polling, because replies are not
reliably much faster than that.  There are occasional >0.5s outlier responses.
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Assignees
No one assigned
Labels
None yet
Projects
None yet
Milestone
0.12
Development

No branches or pull requests
1 participant
@minrk