The syntax for RADOS load-gen is as follows:

# rados -p <pool-name> load-gen

Following is the detailed explanation of preceding command:

• --num-objects: The total number of objects
• --min-object-size: The minimum object size in bytes
• --max-object-size: The maximum object size in bytes
• --min-ops: The minimum number of operations
• --max-ops: The maximum number of operations
• --min-op-len: The minimum operation length
• --max-op-len: The maximum operation length
• --max-backlog: The maximum backlog (in MB)
• --percent: The percentage of read operations
• --target-throughput: The target throughput (in MB)
• --run-length: The total run time in seconds

This command will generate load on the Ceph cluster by writing 50 objects to the RBD pool. Each of these objects and operation lengths is 4 MB in size, with 5% of the read, and test runtime as 60 seconds:

The output has been trimmed for brevity's sake. Once the load-gen command finishes, it cleans all the objects it has created during the test and shows the operation throughput: