bdevperf is an SPDK application 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 lower overhead than the fio plugin, resulting in better performance and efficiency 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. bdevperf also supports a configuration file format similar to FIO. It allows user to create jobs parameterized by filename, cpumask, blocksize, queuesize, etc.
bdevperf's config file format is similar to FIO.
Below is an example config file that uses all available parameters:
Jobs [A] [B] or [C], inherit default values from [global] section residing above them. So in the example, job [A] inherits filename value and uses both Malloc0 and Malloc1 bdevs as targets, job [B] overrides its filename value and uses Malloc1 and job [C] inherits value Malloc0 for its filename.
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 [A] and [B] use its value.
Below is a full list of supported parameters with descriptions.
| Param | Default | Description |
|---|---|---|
| filename | Bdevs to use, separated by ":" | |
| cpumask | Maximum available | CPU mask. Format is defined at CPU mask |
| bs | Block size (io size) | |
| iodepth | Queue depth | |
| rwmixread | 50 | Percentage of a mixed workload that should be reads |
| offset | 0 | Start I/O at the provided offset on the bdev |
| length | 100% of bdev size | End I/O at offset+length on the bdev |
| rw | Type of I/O pattern |
Available rw types: