performance issue, knime hangs

I have recently begun using Knime (2.9.4) on linux.  My first workflow uses some R snippets and R Views.  I am working with a dataset that is about 2.5MB.  Occasionally the Knime application will stall and become unresponsive.  If I use the top command I see that the Knime java process is using 100% of one of the cpu cores.  If I look at the System Monitor I see that this java process is listed as Sleeping and that the Waiting Channel is listed as "futex_wait_queue_me".

Does this suggest something wrong with my computing environment or with the workflow I'm using?

Is there any way to regain responsiveness without losing any unsaved work?

Is there anyway to prevent this from happening in the future?

Thanks, Doug

I left Knime (2.9.4) in this unresponsive condition overnight  and the next day nothing had changed.  I killed the process and created a new workspace and then imported my worflow from the old workspace into the new workspace.  Knime was responsive again, but I had reverted to an earlier version of my workflow.

I spent several more hours building the workflow again and before the end of the next day, Knime has entered this unresponsive state again, cpu core running at 100%, Waiting Channel is listed as "futex_wait_queue_me".  strace reports a lot of this:

$ strace -f -p 6204
Process 6204 attached with 57 threads - interrupt to quit
[pid  8783] restart_syscall(<... resuming interrupted call ...> <unfinished ...>
[pid  8704] restart_syscall(<... resuming interrupted call ...> <unfinished ...>
[pid  6416] futex(0x7f2f586d26ec, FUTEX_WAIT_PRIVATE, 73, NULL <unfinished ...>
[pid  6415] futex(0x7f2f586d42dc, FUTEX_WAIT_PRIVATE, 3, NULL <unfinished ...>
[pid  6205] recvfrom(8, 0x7f30383efac4, 4096, 0, 0, 0) = -1 EAGAIN (Resource temporarily unavailable)
[pid  6205] poll([{fd=8, events=POLLIN}, {fd=43, events=POLLIN}, {fd=137, events=POLLIN}, {fd=93, events=POLLIN}, {fd=92, events=POLLIN}], 5, 0) = 0 (Timeout)


Any suggestions would be appreciated.

Thanks, Doug

Hi Doug, 

There were some mac/linux specific hangs that we have addressed in KNIME 2.10.  I would reccomend an update and see if this resolves the problems that you are running into.  I run on OSX and havn't had this problem at all since updating.  Also, on a semi-related note, we have added an auto-save option to KNIME 2.10, so at the very least, you shouldn't have to worry about losing any unsaved changes should the problem persist. 

Please keep us informed of your progress.