log messages lost when validating script

[VickyXie777]

1. Issue:

sometimes, log messages recorded by log.info() got lost when validating jython script. Only get the table of final statistics, see screenshot.

2. Reproduction steps

1. make A HTTP post request with a large response body
2. validate script on ngrinder console.
3. see validation-0.log on the web console.

3. Screenshots

console stdout:

under the script folder, I found two validation log files, file content of validation-0.log is the same as stdout web console

but validation-0.log1 has log.info we needed,