Managing metadata performance - FSx for Lustre
Lustre metadata performance configurationConsiderations when increasing metadata performanceWhen to increase metadata performance

Managing metadata performance

You can update the metadata configuration of your FSx for Lustre file system without any disruption to your end users or applications by using the Amazon FSx console, Amazon FSx API, or AWS Command Line Interface (AWS CLI). The update procedure increases the number of provisioned Metadata IOPS for your file system.

Note

You can increase metadata performance only on FSx for Lustre file systems created with the Persistent 2 deployment type and a metadata configuration specified.

The increased metadata performance of your file system is available for use within minutes. You can update the metadata performance at anytime, as long as metadata performance increase requests are at least 6 hours apart. While scaling metadata performance, the file system may be unavailable for a few minutes. File operations issued by clients while the file system is unavailable will transparently retry and eventually succeed after metadata performance scaling is complete. You will be billed for the new metadata performance increase after it becomes available to you.

You can track the progress of a metadata performance increase at any time by using the Amazon FSx console, CLI, and API. For more information, see Monitoring metadata configuration updates.

Topics

Lustre metadata performance configuration

The number of provisioned Metadata IOPS determines the maximum rate of metadata operations that can be supported by the file system.

When you create the file system, you choose a metadata configuration mode:

  • For SSD file systems, you can choose Automatic mode if you want Amazon FSx to automatically provision and scale the Metadata IOPS on your file system based on your file system's storage capacity. Note that Intelligent-Tiering file systems don't support Automatic mode.

  • For SSD file systems, you can choose User-provisioned if you want to specify the number of Metadata IOPS to provision for your file system.

  • For Intelligent-Tiering file systems, you must choose User-provisioned mode. With User-provisioned mode, you can specify the number of Metadata IOPS to provision for your file system.

On SSD file systems, you can switch from Automatic mode to User-provisioned mode at any time. You can also switch from User-provisioned to Automatic mode if the number of Metadata IOPS provisioned on your file system matches the default number of Metadata IOPS provisioned in Automatic mode. Intelligent-Tiering file systems only support User-provisioned mode, so you can't switch metadata configuration modes.

Valid Metadata IOPS values are as follows:

  • For SSD file systems, valid Metadata IOPS values are 1500, 3000, 6000, and multiples of 12000 up to a maximum of 192000.

  • For Intelligent-Tiering file systems, valid Metadata IOPS values are 6000 and 12000.

If the metadata performance of your workload exceeds the number of Metadata IOPS provisioned in Automatic mode, you can use User-provisioned mode to increase the Metadata IOPS value for your file system.

You can view the current value of the file system's metadata server configuration as follows:

  • Using the console – On the Summary panel of the file system details page, the Metadata IOPS field shows the current value of the provisioned Metadata IOPS and the current metadata configuration mode of the file system.

  • Using the CLI or API – Use the describe-file-systems CLI command or the DescribeFileSystems API operation, and look for the MetadataConfiguration property.

Considerations when increasing metadata performance

Here are a few important considerations when increasing your metadata performance:

  • Metadata performance increase only – You can only increase the number of Metadata IOPS for a file system; you cannot decrease the number of Metadata IOPS.

  • Specifying Metadata IOPS in Automatic mode not supported – You can't specify the number of Metadata IOPS on a file system that is in Automatic mode. You'll have to switch to User-provisioned mode and then make the request. For more information, see Changing the metadata configuration mode.

  • Metadata IOPS for data written before scaling – When scaling Metadata IOPS beyond 12000, FSx for Lustre adds new metadata servers to your file system. New metadata is automatically distributed across all servers for improved performance. However, existing metadata and subdirectories created before scaling remain on original servers, with no increase in Metadata IOPS.

  • Time between increases – You can't make further metadata performance increases on a file system until 6 hours after the last increase was requested.

  • Concurrent metadata performance and SSD storage increases – You cannot scale metadata performance and file system storage capacity concurrently.

When to increase metadata performance

Increase the number of Metadata IOPS when you need to run workloads that require higher levels of metadata performance than is provisioned by default on your file system. You can monitor your metadata performance on the AWS Management Console by using the Metadata IOPS Utilization graph which provides the percentage of provisioned metadata server performance you are consuming on your file system.

You can also monitor your metadata performance using more granular CloudWatch metrics. CloudWatch metrics include DiskReadOperations and DiskWriteOperations, which provide the volume of metadata server operations that require disk IO, as well as granular metrics for metadata operations including file and directory creation, stats, reads, and deletes. For more information, see FSx for Lustre metadata metrics.