Problem
While using MSR 2.1, I encountered an issue where manual single-step execution didn’t actually perform the step, even though no error was thrown and the interface responded as if it had.
Root Cause
This issue is caused by an advanced setting that discards intermediate data automatically after running, which prevents the step from being executed properly during manual stepping.
Solution
To fix this:
- Go to
Settings > Options > Advanced. - Find the option “Discard data from data flow after running”.
- Change it to “None”.
After that, single-step execution works as expected.
Q&A
Q1: Why doesn’t the step execute even when clicking “Step”?
A1: Because the system discards intermediate data right after running, leaving nothing to feed into the next node or step during manual stepping.
Q2: Is this setting enabled by default in MSR 2.1?
A2: Yes, in many installations, “discard data” is set to a non-None value by default to optimize performance.
Q3: Will changing this setting affect overall performance?
A3: Potentially, yes—retaining data might increase memory usage slightly, but it’s necessary if you want accurate step-by-step debugging.
Summary
If you’re using MSR 2.1 and single-stepping doesn’t work, check your advanced settings and set “Discard data” to “None”. This small change can save hours of debugging confusion.
Hope this helps someone else!
