Katalon repeatedly not responding

I have upgraded my Katalon to 7.4.4 to resolve another issue I was having and now Katalon is becoming non responsive on most save actions and other actions (In some cases just switching windows)

I have already boosted my memory in my ini file from 256 to 512 as suggested in another thread it is not helping. It is making Katalon very frustrating to use. Is there something else I can try to help performance?

Shout out @ThanhTo @duyluong

@trish.goodridge Thanks for posting this, Trish. I’ve been suffering similar issues since 7.2.4 but since nobody else has mentioned anything here (until you) I figured it was something I had caused.

I’m using a table to show the extraordinary weirdness I’m seeing. Each row depicts a KSE 7.2.4 installation - two on the physical machines themselves and two more on virtual machines on the same machines (IOW, each machine has a KSE installed on it, plus a VM with KSE installed on it). All systems are using Windows 10.

Machine Type Location Ram Problem?
PC1 PC n/a 32GB :hot_face:
PC2 PC n/a 16GB :hot_face:
vm1 VM PC1 1GB :sunglasses:
vm2 VM PC2 2GB :sunglasses:

So the VMs are responding fine even with such limited ram available (they are using Hyper-V dynamic memory so the numbers can vary during the lifetime of the vm). Yet the two KSEs with relatively huge amounts of resources available are responding just like you describe.

In addition…

They take a while to start a Test - 5 to 10 seconds for the “Launching test/suite” dialog to appear. The VMs don’t do that either - instant startup of TCs and Suites. Confounding!

I’m moving this to Bug Reports.

Hey Russ,
We are experiencing this on more than one machine.Windows 10 / 64bit and when we tried to uninstall Katalon it would not let us delete the drivers folders saying they were being used. We had deleted most of the install so we know they were not being used by Katalon. We had to reboot in order to remove them. When we re-installed we could record … one time. Then we get the error each time we try to record and by the way we are using Chrome only. It seems we can run tests but recording is not working. I have tried Tools > Web > Terminate running WebDrivers. That says it is shutting them down but we still can’t record. It is very annoying and stopping work for a few of us. Trying to fix one issue has uncovered another.



That sounds like a very different issue.

FYI. There should not be any reason to uninstall Katalon. Once you have rebooted, it is merely sitting on disk doing nothing.

I suspect, when you had trouble removing folders, the JVM or related DLLs were still resident and stuck in memory. I’m not an expert in this area but I would look first at cleaning your project to ensure nothing untoward is causing a problem (perhaps @Brandon_Hein has some ideas here?).

Btw, if you only use Chrome, then this command can be used to clear webdrivers from memory:

taskkill /f /im chromedriver.exe

These might be useful too if you ever change browsers:

taskkill /f /im geckodriver.exe
taskkill /f /im chromedriver.exe
taskkill /f /im IEDriverServer.exe
taskkill /f /im MicrosoftWebDriver.exe

Regarding cleaning your project - delete these two highlighted files and two folders:


Lastly, @duyluong is now handling the general memory issue (if that is indeed the cause).

Thanks Russ, I will do all that asap.FYI The uninstall was a last ditch effort to see if it would stop the poor performance issue.

@duyluong I can confirm that a complete cold reboot clears the issue with the two PCs mentioned in the table above. However, after a period of use (thirty minutes or so) the lagging UI issue returns - once again, only the physical machines… the VMs are fine.

I hate this as a workaround. I rarely reboot a box :wink:

As you can see above, it fixes my issue but only for a short while.

I fear you do have some kind of corruption in your project somewhere. Hopefully the cleanup will do the job.

and let’s see what @Brandon_Hein has to add…

Reading through all of this, we should generally keep in mind that Katalon Studio (the GUI) is entirely separate from the project you build/execute within that studio, at least for the purposes of this topic.

With this in mind, usually the issue is with your project, and not the studio itself. As Russ has mentioned, deleting those folders/files from the project directory, then reopening the project in the studio will often resolve most issues with the project itself. What this does is recompile all code in your project from the .groovy files, which in turn ensures that there are no inconsistencies between the code you’ve typed and the code that actually gets executed at runtime.

If you’re convinced that it’s a problem with the studio, and not with the project code, I would suggest two means of testing that theory:

1.) Open the project in an older version of the studio and see if you still have the same problem(s).
2.) Using your current version of the studio, create a completely new project and test it.


Hey Brandon, I will try this in an older version of Katalon. I did as Russ said and I cleaned up my project I am not sure I am seeing a difference in performance. I am still encountering the issue where I cannot record but I will try the older version and get back to you on both fronts.

Thanks Trish

If it’s just general performance issues, one other thing to try is to disable smart wait. This setting can be found at Project > Settings > Execution > Default Smart Wait

I tried an older version and the recorder launched. I tried 7.3.0 and it works but 7.3.3 and above fails. I also think cleaning up my project fixed my hanging issue.