Is it safe to delete the contents of the Datameer JobHistory folder contained on HDFS under Datameer's private folder?
The deletion of this folder won't alter the executions coming from Datameer. You will lose historic job executions that may be critical when troubleshooting failures in the future.
For example, the default configuration will retain historic execution data for 28 days. If the data is purged manually, all 28 days of stored Job Traces will be inaccessible.
If you are uncomfortable with the amount of data being stored in /path/to/datameer/jobhistory, you may consider lessening the amount of days we retain logging information.
This setting can be found in the <datameer>/conf/default.properties file.
Feel free to adjust this value down and monitor your disk usage.