Benchmarking Ceph block performance

Ceph includes the rbd bench-write command to test sequential writes to the block device measuring throughput and latency.

The default byte size is 4096, the default number of I/O threads is 16, and the default total number of bytes to write is 1 GB. These defaults can be modified by the --io-size, --io-threads and --io-total options respectively.

Prerequisites

  • A running IBM Storage Ceph cluster.

  • Root-level access to the node.

  • Run the write performance test against the block device:

    Example 

    [root@host01 ~]# rbd bench --io-type write image01 --pool=testbench

bench-write  io_size 4096 io_threads 16 bytes 1073741824 pattern seq
  SEC       OPS   OPS/SEC   BYTES/SEC
    2     11127   5479.59  22444382.79
    3     11692   3901.91  15982220.33
    4     12372   2953.34  12096895.42
    5     12580   2300.05  9421008.60
    6     13141   2101.80  8608975.15
    7     13195    356.07  1458459.94
    8     13820    390.35  1598876.60
    9     14124    325.46  1333066.62
    ..