Performance considerations

This page provides guidance on configuring your Google Cloud Managed Lustre environment to obtain the best performance.

Performance metrics

Metric Result
Throughput Up to 1 TBps
IOPS Thousands of IOPS per TiB

VPC network maximum transmission unit (MTU)

When creating your VPC network, setting the value of mtu (maximum transmission unit, or the size of the largest IP packet that can be transmitted on this network) to the maximum allowed value of 8896 improves performance up to 10% compared to the default value of 1460 bytes.

You can see the current MTU value of your network with the following command:

gcloud compute networks describe NETWORK_NAME --format="value(mtu)"

The MTU value of a network can be updated after the network has been created, but there are important considerations. See Change the MTU of a network for details.

Compute Engine machine types

Network throughput can be affected by your choice of machine type. In general, to obtain the best throughput:

  • Increase the number of vCPUs. Per-instance maximum egress bandwidth is generally 2 Gbps per vCPU, up to the machine type maximum.
  • Select a machine series that supports higher ingress and egress limits. For example, C2 instances with Tier_1 networking support up to 100Gbps egress bandwidth. C3 instances with Tier_1 networking support up to 200Gbps.
  • Enable per VM Tier_1 networking performance with larger machine types.

For detailed information, refer to Network bandwidth.

Testing single-client performance

To test read and write performance from a single Compute Engine client, use the fio (Flexible I/O tester) command line tool.

  1. Install fio:

    Rocky 8 

    sudo dnf install fio -y

    Ubuntu 20.04 and 22.04 

    sudo apt update
sudo install fio

  2. Run the following command:

    fio --ioengine=libaio --filesize=32G --ramp_time=2s \
--runtime=5m --numjobs=16 --direct=1 --verify=0 --randrepeat=0 \
--group_reporting --directory=/lustre --buffer_compress_percentage=50 \
--name=read --blocksize=1m --iodepth=64 --readwrite=read

The test takes approximately 5 minutes to complete. When finished, the results are displayed. Depending on your configuration, you can expect throughput up to your VM's maximum network speed, and thousands of IOPS per TiB.