You may see files that have no content of very little content in the log4j folder. Some examples are .log4j and _policies.log4j. These files are related to log4jv2 and the sequence that AutoPilot initializes. These small files occur during early phases of initialization and have no useful content. They can be ignored. It is not possible to delete them when AutoPilot is running as they will remain in use. The associated gz files can be deleted but since these files are typical only 1 KB in size, they can easily be ignored with no adverse impact.
You may also see empty files with other names, for example DOMAIN_SERVER_policies.log4j. This is also related to logging and these files are created during initialization of the logging environment. However, it is possible that no logging to these files is done so the files remain empty. As with the files above, they can be ignored with no adverse impact.