Cloud Block Storage is a highly available, highly reliable, low-cost, and customizable network block device that can be used as a standalone and expandable disk for CVMs. It provides data storage at the data block level and uses a three-copy distributed mechanism to ensure data reliability. Cloud Block Storage provides three types of cloud disks, SSD cloud storage, premium cloud storage and HDD cloud storage. Disk performance, features and pricing vary by type, you can choose according to the requirements of your deployed applications.
- SSD cloud storage: SSD cloud disks are based on NVMe SSD storage, and use a three-copy distribution mechanism to provide high-performance storage with low latency, high random IOPS, high throughput I/O capability, and data security up to 99.9999999%. SSD disks are suitable for scenarios with relatively high requirements for I/O performance.
- Premium cloud storage: Premium cloud storage by Tencent Cloud is a hybrid storage type. It provides a high-performance storage capability that approaches SSD, and uses a three-copy distribution mechanism to ensure data reliability. Premium cloud storage is suitable for mid- and small-sized applications with high data reliability requirements and normal performance requirements, as well as for mid- to small-sized relational database applications, such as MySQL, SQL Server, and PostgreSQL.
- HDD cloud storage: HDD cloud disk is the first generation cloud disk type provided by Tencent Cloud. It is suitable for business scenarios with low I/O loads where data is not accessed frequently. It uses magnetic storage, and a three-copy distribution mechanism to implement highly reliable data storage.
Performance differences between SSD cloud storage, Premium cloud storage, and HDD cloud storage are as follows:
| SSD cloud storage | Premium cloud storage | HDD cloud storage | |
|---|---|---|---|
| Random IOPS | Maximum random IOPS = 1800 + Storage capacity (GB) × 30 Maximum random IOPS does not exceed 26000 |
Maximum random IOPS = 1800 + Storage capacity (GB) × 8 Maximum random IOPS does not exceed 6000 |
Provide specification options of 10GB - 16000GB and random IOPS performance of up to several hundreds |
| Throughput (MB/s) | Maximum throughput = 120 + Storage capacity (GB) × 0.2 Maximum throughput does not exceed 260MB/s |
Maximum throughput = 100 + Storage capacity (GB) × 0.15 Maximum throughput does not exceed 150MB/s |
Support I/O throughput performance of 50MB/s |
| Latency | <3ms | <4ms | - |
Main difference between SSD cloud storage and Premium cloud storage is I/O requirement.
**SSD cloud storage is more suitable for intensive I/O scenarios, such as:
- High performance, high data reliability: Suitable for high-load, mission-critical business systems. Provide three-copy data redundancy, and comprehensive capabilities for data backup, snapshots, and recovery within seconds.
- Mid- and large-sized databases: Support mid- and large-sized relational database applications that contain tables with millions of rows, such as MySQL, Oracle, SQL Server, and MongoDB.
- Large-sized NoSQL: Satisfy storage performance requirements of NoSQL businesses such as HBase and Cassandra.
- Core business systems: For I/O-intensive applications and other core business systems with high requirements for data reliability .
- Big Data analysis: Provide distributed processing capabilities for data at TB and PB levels, suitable for data analysis, data mining, business intelligence, and more.
Premium cloud storage is primarily suitable for the following data scenarios:
- Suitable for mid- to small-sized databases and web servers, provide long-term and stable I/O performance.
- Suitable for scenarios with balanced requirements for storage capacity and performance, such as enterprise office services and log services.
- Satisfy I/O requirements for core business testing and developing joint testing environments.
Pricing for the three types of cloud disks varies by region. Generally, high-performance SSD cloud storage is the most expensive. For more billing information on the three types of cloud storage, see Price Overview.
