The StorPool FIO Test Suite

This is a description of the disk test suite found in the /usr/share/doc/storpool/examples/fio/ directory of a StorPool installation.

Overview

The test suite consists of template configurations for the fio tool and several tools to run tests. The run_quick tool may be used to run a predefined set of tests on a single disk or volume, the run_one tool only runs a single test, the get_res tool examines the res/ directory populated by the run_* ones and displays the results as a series of lines containing comma-separated values, and the pretty_print tool outputs these CSV lines in a human-readable format.

Prerequisites

The StorPool fio test suite expects that the fio tool is installed, along with a Perl interpreter and the Data::Dumper and JSON::XS Perl modules. To check whether they are installed, run the following commands:

# which fio
# perl -MData::Dumper -MJSON::XS -e 'print "OK\n"'

On RedHat-derived distributions, run the following commands as root to make sure that these prerequisites are installed:

# yum install epel-release
# yum install --enablerepo=epel fio perl-autodie perl-Data-Dumper perl-JSON-XS

On Debian-derived systems, run the following command as root:

# apt-get install fio libjson-xs-perl

Quick Start: the run_quick tool

To run a suite of predefined tests on a single disk or volume, use the run_quick tool and pass it a single parameter: the path to the block device:

# ./run_quick /dev/storpool/test-volume

When testing the performance of volumes in a StorPool cluster, create the volume and attach it to this host beforehand:

# storpool volume test-volume create template hybrid size 60G
# storpool attach volume test-volume here

The run_quick tool will run the tests listed in the tests file; currently this includes:

• rand-w-4k-64
• fill
• lat-r-4k-1
• seq-r-1M-64
• rand-r-4k-64
• seq-w-1M-64
• lat-w-4k-1
• rand-rw-4k-64

It will then use the get_res and pretty_print tools to output some information about the test results in a human-readable format.

Run tests one by one: the run_one tool

To run a single test, use the run_one tool and pass it the name of the test and the path to the block device to run the test on:

# ./run_one seq-r-1M-64 /dev/storpool/test-volume

The get_res and pretty_print tools may be then used to output the results:

# ./get_res
# ./get_res | ./pretty_print

To see what the fio tool would do without actually running the test, run fio with the --showcmd option, also passing it the test template name as a job name:

# fio --showcmd template/rand-r-8k-64

Test template names

The get_res tool extracts some information from the test results depending on the template name, e.g. throughput information for tests named seq-r-* and seq-w-*, I/O operations per second information for tests named rand-r-*, etc. The template names are expected to consist of several components:

• test type: seq for sequential read/writes, rand for random read/writes, lat for I/O latency tests, latpio for combined I/O latency and I/O operations per second output
• I/O operation direction: r for reads, w for writes, rw for both
• I/O operation block size: 4k, 8k, 1M, etc.
• queue depth (see the fio tool documentation): 1, 2, 16, 512, etc.

Writing your own test templates

There are two main rules for writing your own templates: adhere to the naming convention described above, and use any fio options except ones governing the output format and the disk device to test. Other than that, the test template is a standard fio job definition.