Scale out a file system

Prerequisites

You have an existing CPFS file system. For more information, see Create a file system.

Usage notes

• You can scale out a file system only when it is in the Running state.

• The time required for a scale-out operation depends on the scaling step size. A 1,200 GiB increment typically takes about 10 minutes. A larger scaling step size increases the duration, up to a maximum of approximately 30 minutes.

• You can only scale out a file system. Scaling in is not supported. For CPFS file systems with a 100 MB/s/TiB or 200 MB/s/TiB baseline throughput, the scaling step size is 2,400 GiB in the China (Ulanqab) region and 1,200 GiB in other regions. The maximum capacity of a file system is 1 PiB.

• When a file system approaches its capacity limit, high file fragmentation can degrade performance. Scale out the file system before its usage reaches 90%.

• For optimal performance, perform data balancing after you scale out a CPFS file system. The data balancing process consumes some disk and network bandwidth, which might cause a minor decrease in performance. To use this feature, submit a ticket.

  • The time required for data balancing is proportional to the amount of existing data, and the process can be lengthy for large volumes.

  • In cases of extreme data imbalance, the total capacity and used space reported by the df command and in the NAS console may appear to decrease. This apparent change does not affect data security or access performance.

  • Without data balancing, application latency may increase as more data is written to the file system.

Procedure

1. Log on to the NAS console.

2. In the left-side navigation pane, choose File System > File System List.

3. In the top navigation bar, select a region.

4. Find the target file system and click > Upgrade in the Actions column.

   Note

   You can only scale out a file system. Scaling in is not supported. For CPFS file systems with a 100 MB/s/TiB or 200 MB/s/TiB baseline throughput, the scaling step size is 2,400 GiB in the China (Ulanqab) region. For other regions, the scaling step size is 1,200 GiB. The maximum capacity of a file system is 1 PiB.

5. In the Upgrade panel, drag the slider in the Capacity of CPFS File System section to adjust the capacity.

   Note

   To ensure stable performance after a scale-out, increase the total capacity by at least 10%.

6. Click Buy Now and follow the on-screen instructions to complete the purchase.

API

You can also scale out a CPFS file system by calling the UpgradeFileSystem API operation.

Related topics

• To check the capacity usage of your file system, see View CPFS capacity monitoring data.

• To receive timely alerts about file system capacity and performance, configure alert rules for key metrics. For more information, see Configure a basic alert rule and Configure an advanced alert rule.