fio

rw=read: sequential read
rw=write: sequential write
rw=randread: random read
rw=randwrite: random write
rw=rw: sequential mixed read/write
rw=randrw: random mixed read/write

fio is an open-source I/O pressure test tool used to test the storage I/O performance. It supports multiple engines. In this document, the RBD engine is used as an example. fio supports flexible configurations and concurrent tests on multiple clients (server and client modes).

Table 1 describes the fio parameters.

**Table 1** fio parameters
Parameter	Description
ioengine	I/O engine fio supports the following engines: cpuio, mmap, sync, psync, vsync, pvsync, pvsync2, null, net, netsplice, ftruncate, filecreate, libaio, posixaio, falloc, e4defrag, splice, rados, rbd, mtd, sg, io_uring
clientname	Ceph user
pool	Ceph storage pool
rbdname	Ceph RBD image name
direct	I/O type. The value 1 indicates non-buffered I/O, whereas the value 0 indicates buffered I/O.
rw	Read/Write type rw=read: sequential read rw=write: sequential write rw=randread: random read rw=randwrite: random write rw=rw: sequential mixed read/write rw=randrw: random mixed read/write
bs	I/O block size
size	Read/Write data volume
iodepth	Queue depth
numjobs	Number of job copies
runtime	fio execution time
time_based	Indicates whether fio runs for the duration specified by runtime even if the files have been completely read or written.
log_avg_msec	Log collection interval, in milliseconds
ramp_time	Running time required before any performance information is logged. This parameter ensures that the results are logged only after the performance is stable and minimizes the runtime required for stable results.
thread	By default, fio uses fork() to create jobs. If this option is enabled, fio uses pthread_create to create threads.
rwmixread	Read/write ratio in a mixed read/write test.
stonewall	Indicates whether to start a task only after the previous task is complete when a job file contains multiple test tasks.

fio is a stable test tool. For details about how to use fio and the parameters, see the user guide.

Parent topic: Test Tools