How to Measure the Performance of a Cloud Disk?
The following metrics are generally used to describe the performance of storage devices:
- IOPS: Number of reads/writes per second with units in counts. The underlying driver type of the storage device determines different IOPS.
- Throughput: the amount of read and write data per second in MB/s.
- Delay: the time from sending I/O operation to receiving and confirmation in seconds.
How to Test Disk Performance?
It is recommended to use FIO to perform stress testing and verification on the cloud disk. For specific operations, see How to Measure the Performance of a Cloud Disk.
Will the I/O Size Read and Written by the Application Affect My IOPS Performance?
Yes. For a given resource, the IOPS you get depends on the I/O size of your application's read-and-write operations. Usually, the IOPS performance of a hard disk can be fully applied when reading and writing in small blocks (for example, I/O size is 256 KB).
Will the I/O Size Read and Written by the Application Affect My Throughput Performance?
Yes. For a given resource, the throughput you get depends on the I/O size of your application's read-and-write operations. Usually, the throughput performance of a hard disk can be fully applied when reading and writing in large blocks (for example, I/O size is 1 MB).
Can Multiple Hard Disks Be Logically Combined into One for Better Performance?
Yes, you can stripe multiple cloud disks attached to a CVM and balance the I/O load across multiple disks to enhance I/O parallelism and achieve higher performance beyond that of a single disk. For details, see Building a Logical Volume in LVM with Multiple Elastic Cloud Disks.