bdevperf is an SPDK application that is used for performance testing of block devices (bdevs) exposed by the SPDK bdev layer. It is an alternative to the SPDK bdev fio plugin for benchmarking SPDK bdevs. In some cases, bdevperf can provide much lower overhead than the fio plugin, resulting in much better performance for tests using a limited number of CPU cores.
bdevperf exposes command line interface that allows to specify SPDK framework options as well as testing options. Since SPDK 20.07, bdevperf supports configuration file that is similar to FIO. It allows user to create jobs parameterized by filename, cpumask, blocksize, queuesize, etc.
Bdevperf's config file is similar to FIO's config file format.
Below is an example config file that uses all available parameters:
[C], inherit default values from
[global] section residing above them. So in the example, job
filename value and uses both
Malloc1 bdevs as targets, job
[B] overrides its
filename value and uses
Malloc1 and job
[C] inherits value
Malloc0 for its
Interaction with CLI arguments is not the same as in FIO however. If bdevperf receives CLI argument, it overrides values of corresponding parameter for all
[global] sections of config file. So if example config is used, specifying
-q argument will make jobs
[B] use its value.
Below is a full list of supported parameters with descriptions.
|filename||Bdevs to use, separated by ":"|
|cpumask||Maximum available||CPU mask. Format is defined at CPU mask|
|bs||Block size (io size)|
|rwmixread||Percentage of a mixed workload that should be reads|
|offset||Start I/O at the provided offset on the bdev|
|length||100% of bdev size||End I/O at |
|rw||Type of I/O pattern|
Available rw types: