These files are used by FIO (Flexible IO Tester) to control IO testing. Each file runs a different test, each test will allocate four 4GB files to be used as IO targets. The files created are the same for each test so only a set of four files will be created in total.
All the tests bypass the pagecache to avoid false positives when doing IO, the idea of these tests is to verify disk performance.
To run FIO simply move into the directory you want to test and run:
fio /path/to/config/file
This test runs SEQUENTIAL IO using 4K blocksize, with a smaller blocksize this test is suited for IOPS testing.
This test runs SEQUENTIAL IO using 1M Blocksize, a larger blocksize will yield higher throughput and lower IOPS.
This test runs SEQUENTIAL IO using 4K blocksize, with a smaller blocksize this test is suited for IOPS testing.
This test runs SEQUENTIAL IO using 1M Blocksize, a larger blocksize will yield higher throughput and lower IOPS.
Each file can be changed to match a specific need, settings on the global section affect the entire test vs settings specified in the file section will only affect that specific file.
For example:
[global]
name=read-nocache-random
rw=randread
group_reporting=1
bs=4K
direct=1
numjobs=4
time_based=1
runtime=180
iodepth=64
ioengine=libaio
[file1]
size=4G
filename=fio.file.1
For global setting, the test uses 4K blocksize, ignores pagecache through the use of direct IO, spawns 4 jobs per file, uses a queue depth of 64 and uses the libaio engine.
More info regarding FIO: FIO MANUAL