The log file in WinSCP is very large after running, how can I reduce it?

My bat code is below:
The log file in WinSCP is very large, about 22Mb after running, please help me get the small log file, hope not greater than 1Mb.
The log file should include error information, the number of uploaded files, etc.

You didn't tell us much about the log. So we cannot know if the log is large because WinSCP does many operations or because you have enabled debug logging inadvertently.

Use /loglevel to change the log level.
https://winscp.net/eng/docs/commandline#logging

You should isolate your script from GUI configuration, so that logging setting changes in the GUI do not impact your script:
https://winscp.net/eng/docs/scripting#configuration

You might also consider using XML logging:
https://winscp.net/eng/docs/logging_xml

The code change below:
the log file reduce to 428kb. Is /xmlgroups set correctly?
Thanks reply.

Correctly for what? If you wanted to enable the group XML log element, then yes.