Disk types
Updated at：2025-11-03
Disk type parameters
You may refer to the following performance parameters to select a suitable cloud disk type. These parameters include core metrics such as single-disk capacity, random IOPS, throughput, and more.
| CDS type | Single-disk capacity (GB) | Random IOPS | Throughput (MBps) | Access latency (ms) |
|---|---|---|---|---|
| Enhanced SSD_PL3 | 1261~65536 | ·Maximum 1,000,000IOPS = min{1800 + 50 × capacity, 1,000,000} | ·Maximum 4,000Throughput = min{120 + 0.5 × Capacity, 4,000} | Microsecond (μs) level |
| Enhanced SSD_PL2 | 461~65536 | ·Baseline IOPS = min{1800 + 50 × capacity, 100,000} ·Additional IOPS = min{preconfigured IO, 100,000} ·Total disk IOPS = min{baseline IO + preconfigured IO, 100,000} | ·Baseline throughput = min{120 + 0.5 × capacity, 750} ·Additional throughput = min{preconfigured IO × 16 / 1024, 1000} ·Total disk throughput = min{baseline throughput + preconfigured throughput, 1000} | < 1 |
| Enhanced SSD_PL1 | 5~65536 | ·Maximum 50,000IOPS = min{1800 + 50 × capacity, 50,000} | ·Maximum 350Throughput = min{120 + 0.5 × Capacity, 350} | < 2 |
| General-purpose SSD | 50~65536 | ·Maximum 25,000IOPS = min{1,800 + 30 × capacity, 25,000} | · Maximum 300Throughput = min{120 + 0.5 × Capacity, 300} | < 2 |
| High-performance cloud disk | 5~65536 | ·Maximum 5,000IOPS = min{1,800 + +8 × capacity, 5,000} | · Maximum 140Throughput = min{100 + +0.15 × Capacity, 140} | < 3 |
Instructions for use
- Enhanced SSD_PL3 is recommended to be mounted on g7, ga3, and newer generations of cloud server models; otherwise, performance cannot be guaranteed.
- Enhanced SSD_PL2 is recommended to be mounted on g5, c5 and ga2, and newer generations of cloud server models, and it is recommended that the core count be greater than 16; otherwise, performance cannot be guaranteed. Enhanced SSD_PL2 supports Performance Preconfiguration, allowing you to adjust disk performance at any time to flexibly respond to changes in business requirements;
- Previous-generation cloud disks and general-purpose HDDs are currently in the process of natural obsolescence. It is recommended that you purchase other types of cloud disks. For existing previous-generation cloud disks, capacity expansion may fail in some regions. Please change the disk type to a high-performance cloud disk or another higher-performance type at the same time. Disk type changes are performed online and do not affect the disk’s read/write processes;
- Cloud disk performance improves linearly with capacity. For instance, a 100 GB high-performance cloud disk offers up to 2,600 random IOPS and 115 MBps throughput. In comparison, previous-generation cloud disks provide 30-40 MBps throughput, several hundred IOPS, and latency under 10 milliseconds.
- The data reliability of all cloud disks is 99.9999999%;
- When a cloud server reads from or writes to CDS, a certain amount of network bandwidth is occupied. To optimize CDS read/write performance, we provide additional dedicated CDS bandwidth for cloud servers to ensure CDS throughput performance: (1) Each CPU core can enjoy 16 MB/s of dedicated CDS bandwidth. For example, if you purchase a 16-core cloud server, you can get 256 MB/s of dedicated CDS bandwidth; (2) Dedicated CDS bandwidth is calculated separately for read and write requests. For example, a 16-core cloud server has 256 MB/s of read bandwidth and 256 MB/s of write bandwidth; (3) The actual available CDS bandwidth of a cloud server includes both dedicated bandwidth and shared bandwidth. Therefore, the actual throughput of CDS is usually much higher than the throughput allowed by the dedicated bandwidth;