HP c-Class Performance Tuning manual System performance, Verifying Linux system performance

System performance

Verifying Linux system performance

To verify Linux system performance with an IO Accelerator, HP recommends using the fio benchmark. This benchmark was developed by Jens Axboe, a Linux kernel developer. Fio is included in many distributions, or can be compiled from source. The latest source distribution (http://freshmeat.net/projects/fio) requires having the libaio development headers in place. For step-by-step instructions on compiling fio from source, see "Compiling the fio benchmark (on page 23)."

To test the raw performance of the IO Accelerator, HP recommends using raw block access. The best way to verify system performance is to run the fio tests in "Running fio tests (on page 6)."

CAUTION: The write tests destroy all data that currently resides on the IO Accelerator.

NOTE: For best performance on the IO Accelerator, use driver stack 2.1.0 or later.

Running fio tests

The sample jobs include the following four fio tests:

•One-card write bandwidth

•One-card read IOPS

•One-card read bandwidth

•One-card write IOPS

The following benchmarks are designed for maximally stressing the system and detecting performance issues, not to highlight IO Accelerator performance.

Benchmark tests

# Write Bandwidth test

$ fio --filename=/dev/fioa --direct=1 --rw=randwrite --bs=1m --size=5G --numjobs=4 --runtime=10 --group_reporting --name=file1

# Read IOPS test

$ fio --filename=/dev/fioa --direct=1 --rw=randread --bs=4k --size=5G --numjobs=64 --runtime=10 --group_reporting --name=file1

# Read Bandwidth test

$ fio --filename=/dev/fioa --direct=1 --rw=randread --bs=1m --size=5G --numjobs=4 --runtime=10 --group_reporting --name=file1

# Write IOPS test

System performance 6