...
The efficiency score is the number of unique tape file accessed divided by the number of requests to access these files:
Access 10 files with 10 request requests = 100% score
Access 1 file with 10 request requests = 10% score
We would recommend you to read Guidelines to write efficient MARS requests, but please do contact our ServiceDesk via email (servicedesk@ecmwf.int) or our support portal if you need any further advice.