Slow work of WEKA Nodes


I download ne KNIME 2.7 and import my flow with WEKA Nodes. I see, that nodes now uses more heap, because I have errors "Java heap error" (the same flow work without any problems in 2.6). More, KNIME become work slowly when WEKA nodes executes: I can wait about half of minute for tab change after mouse click.

And, thank you, I haven't any crashes KNIME 2.7 in Linux after day of usage.


Hi Max,

I think you should increase the memory reserved for KNIME. The behaviour you described can be a symptom of not enough max memory for the JVM. Before OutOfMemoryErrors the JVM tries to garbage collect more often, which makes it irresponsive. I would suggest to increase the -Xmx parameter in the config file.



Thank you for reply. I used both 2.6 and 2.7 with same XMX value - 1536Mb on laptop with 2 Gb memory. KNIME 2.6 work fast with WEKA. KNIME 2.7 - very slow (not freezing, but near from it). And work slowly not node, what I saw earlier and understand why it happens,  KNIME "freezes", I couldn't work with other nodes and flows. And it happens in workflow, imported from 2.6.3, on the same nodes.


For test: it's my workflow (sorry for some inaccuracy). It more than 4 Mb, so I use google drive.

Try to execute metanode "Learning curves" in "All Data" metanode. In my case it work fine in 2.6.4 and I couldn't execute it at 2.7.0.