About config file options

I’m looking at a config file.

storage:

wiredTiger:

configString: <.String>
checkpointSizeMB: <.Int>
statisticsLogDelaySecs: <.Int>

I saw these three options.
I looked up the manual for exactly what this option says, but it didn’t come out, so I’d like to know the description of these options.
Or are these options real?

One of the param is superseded by a new param and it is made hidden as per this ticket
Others not sure

https://jira.mongodb.org/browse/DOCS-7581

Hi @Kim_Hakseon,

Those options are not listed as per the official documentation in storage options for MongoDB 4.4. If you don’t mind, could you tell us where did you find those options, and for what MongoDB version?

Best regards,
Kevin

I asked because it was in the sample config file that I received somewhere to study.