Could Not Save Workflow - Urgent

[supersharp]

Hi, if anyone can help it would be appreciated.
I keep getting errors like this when trying to save workflows. Usually this happens after a period of absence from the computer, there is just no way to save the workflow, and neither does it allow you to save as a different name, publish to Server, or export. This is particularly a concern when changes have been made and there simply is no way to know what those changes are and whether they will be saved or not. Please advise?

2020-09-14 23:58:47,668 : FATAL : ModalContext : : InplaceSaveRunnable : : : File not found - this exception will be re-thrown as an InterruptedException.
java.io.FileNotFoundException: C:\Users\AppData\Local\Temp\knime_GL_Bank_Prep_fo83972\knime_container_20200913_7657928779082410725.bin.snappy (The system cannot find the file specified)
at java.io.FileInputStream.open0(Native Method)
at java.io.FileInputStream.open(FileInputStream.java:195)
at java.io.FileInputStream.(FileInputStream.java:138)
at org.knime.core.data.container.Buffer.addToZipFile(Buffer.java:1870)
at org.knime.core.data.container.BufferedContainerTable.saveToFile(BufferedContainerTable.java:211)
at org.knime.core.data.container.RearrangeColumnsTable.saveToFile(RearrangeColumnsTable.java:680)
at org.knime.core.node.BufferedDataTable.save(BufferedDataTable.java:640)
at org.knime.core.node.FileNodePersistor.saveBufferedDataTable(FileNodePersistor.java:1438)
at org.knime.core.node.FileNodePersistor.savePort(FileNodePersistor.java:1343)
at org.knime.core.node.FileNodePersistor.savePorts(FileNodePersistor.java:1247)
at org.knime.core.node.FileNodePersistor.save(FileNodePersistor.java:1201)
at org.knime.core.node.workflow.FileNativeNodeContainerPersistor.save(FileNativeNodeContainerPersistor.java:518)
at org.knime.core.node.workflow.FileSingleNodeContainerPersistor.save(FileSingleNodeContainerPersistor.java:598)
at org.knime.core.node.workflow.FileWorkflowPersistor.saveNodeContainer(FileWorkflowPersistor.java:2175)
at org.knime.core.node.workflow.FileWorkflowPersistor.saveContent(FileWorkflowPersistor.java:1930)
at org.knime.core.node.workflow.FileWorkflowPersistor.save(FileWorkflowPersistor.java:1844)
at org.knime.core.node.workflow.WorkflowManager.save(WorkflowManager.java:8673)
at org.knime.workbench.editor2.InplaceSaveRunnable.save(InplaceSaveRunnable.java:92)
at org.knime.workbench.editor2.AbstractSaveRunnable.run(AbstractSaveRunnable.java:103)
at org.eclipse.jface.operation.ModalContext$ModalContextThread.run(ModalContext.java:122)
2020-09-14 23:58:47,699 : ERROR : main : : WorkflowEditor : : : Could not save + workflow: File access problems: C:\Users\AppData\Local\Temp\knime_GL_Bank_Prep_fo83972\knime_container_20200913_7657928779082410725.bin.snappy (The system cannot find the file specified)
java.lang.InterruptedException: C:\Users\AppData\Local\Temp\knime_GL_Bank_Prep_fo83972\knime_container_20200913_7657928779082410725.bin.snappy (The system cannot find the file specified)
at org.knime.workbench.editor2.AbstractSaveRunnable.handleRunExceptionCleanUp(AbstractSaveRunnable.java:153)
at org.knime.workbench.editor2.AbstractSaveRunnable.run(AbstractSaveRunnable.java:109)
at org.eclipse.jface.operation.ModalContext$ModalContextThread.run(ModalContext.java:122)

[mlauber71]

@supersharp there was a lengthy discussion that seemingly involved similar problems.

Execute failed: Cannot read file "knime_container_20200301_1905559478659870280.bin.snappy"

For @qqilihq one helpful step was to switch the internal compression to gzip. That would obviously only work after a restart.

If you have a workflow open and cannot save it these things come to my mind

• try opening a fresh WF and copy/paste the whole thing and try saving that without internal data storage
• convert the whole thing or very important parts into a meta node and share that
• take screenshots so at least you would know the structure of what you did

This is not very elegant but might preserve some of your work.

[supersharp]

Thanks mlauber71. I ended up copying the workflow to a new workflow and saving that as a new version (phew!). I’ll work on changing the internal compression to gzip and check out the additional link - thanks!

[supersharp]

@mlauber71 - the change of the .ini to gzip worked for the original problem I had, but had unintended consequences (https://docs.knime.com/2019-12/analytics_platform_workbench_guide/index.html#table-knime-ini).

Now, previous workflows built when the compression was the default ‘SNAPPY’ do not seem to run properly, and cause KNIME to freeze (which is very odd for KNIME). Upon changing the .ini file back to SNAPPY my workflow ran fine. Now my issue is I don’t know which files were run with SNAPPY and which were run with GZIP compression, some workflows were partly built with both compression setups. I have been noticing a lot more failures with my workflows and not sure how to get them back to normal, pretty sure this is the cause.

@knime - I’d be happy to provide details of this problem to help it be addressed!

[mlauber71]

@supersharp

Upon changing the .ini file back to SNAPPY my workflow ran fine. Now my issue is I don’t know which files were run with SNAPPY and which were run with GZIP compression, some workflows were partly built with both compression setups.

This indeed does sound strange. Typically if you reset a workflow I would expect it to revert to the default compression next time. And at least with zip or parquet KNIME seems to be happy with using both. Cf. also this entry:

Knime is slowing down

That is certainly odd. To the best of my knowledge, there haven’t been any recent major changes to KNIME that are known to have a degrading effect on performance. From my experience, the most dominating performance factor in KNIME is the materialization of intermediate data tables on disk. Have you noticed the performance of your hard disk degrading independently of KNIME? While we have some performance improvements for KNIME in the pipeline, here are some small adjustments you can try out: Y…

Question is if you reset a workflow would it then run Ok.

If a workflow is stored with data in it you could:

• export it into a knwf file without data stored
• rename the original WF
• import the stored one

Now you should have a working WF.

Then could you tell us more about your system and setup and versions. And maybe provide a fresh log file set to debug. Maybe someone from KNIME then can weight in.

A meta collection about KNIME and performance and performance tuning and some...

[beginner]

Just commenting because I had this same issue on a new workflow just recently and I’m not using parquet as storage, eg. the default with I assume to be zip.

I also applied the copy nodes to new workflow trick and that resolved the issue but there sure seems to be some new, obscure issue happening with KNIME 4.2.

[ZTavana]

It happens to me all the time and it is weird that the solution is to copy the whole WF to a new one and save it…I have done this in multiple occasions but that should not be long term solution.

[beginner]

Agree. It’s weird. I have had it 2-3 times and I use KNIME often. In my case as far as I remember it happened with a new, not previously saved workflow.