tencent cloud

Feedback

Selection Guide

Last updated: 2024-05-14 17:08:50
    Before purchasing a TencentDB for MySQL instance, it is important to learn about the features of different instances so that you can select one that meets your business requirements.

    Instance Information

    Prior to purchasing a TencentDB for MySQL instance, you must consider factors such as cost, performance, workload, and usage scenarios, so that you can select a suitable instance with optimal costeffectiveness. Since the database storage engine, instance architecture, storage type, and resource isolation policy are intricately intertwined and are mutually impacted, you may be confused when selecting an instance. This document briefly introduces these components to assist you in selecting an appropriate instance.

    1. Database Storage Engine

    A storage engine refers to the type of tables. The storage engine of database determines the manner in which tables are stored in a computer.
    InnoDB: The most frequently used OLTP storage engine, uses multi-version concurrency control (MVCC) and row-level locking technologies, offering high performance and reliable processing capabilities. In comparison to other MySQL storage engines, InnoDB offers functions including data foreign key and rollback, ensuring better data integrity. It also provides higher-level query functionalities. InnoDB kernel has been optimized a lot by Tencent Cloud and therefore has great performance advantages and is extensively applied in scenarios that involve high concurrency and require high performance.
    RocksDB: A popular high-performance persistent key-value (KV) storage based on which Tencent's TXSQL team develops TXRocks, a transactional storage engine. TXRocks, benefitting from the LSM Tree storage structure of RocksDB, has significantly reduced the waste caused by InnoDB's half-full page and fragmentation mechanisms, and utilized compact format storage. In this way, compared with InnoDB, TXRocks provides similar performance with half the storage space. It's more suitable for business scenarios that involve a large volume of data and require high read and write performance.

    2. Instance Architecture

    TencentDB for MySQL supports four types of instance architectures: single-node, two-node, three-node, and Cluster Edition.
    
    Architecture
    Description
    Applicable Scenarios
    Single-Node
    Supported versions: MySQL 5.7 and 8.0.
    Node: Single Node.
    Personal learning, micro-websites, non-core small-scale enterprise systems, and the development and testing environments of large and medium-sized corporations.
    Two-Node
    Supported versions: MySQL 5.6, 5.7, and 8.0.
    Nodes: One Primary and One Standby.
    Primary-Standby Replication Mode: Asynchronous (default) and Semi-Synchronous
    Gaming, internet, IoT, retailing e-commerce, logistics, insurance, and securities, etc.
    Three-Node
    Supported versions: MySQL 5.6, 5.7, and 8.0.
    Nodes: One Primary and Two Standbys.
    Primary-Standby Replication Mode: Asynchronous (default), Strong-synchronous, and Semi-Synchronous
    Gaming, internet, IoT, retailing e-commerce, logistics, insurance, and securities, etc.
    Cluster Edition
    Supported Versions: MySQL 5.7, 8.0.
    Nodes: One read-write node and up to five read-only nodes.
    Primary-Replica Replication Method: Asynchronous, and semi-synchronous (default).
    Gaming, internet, IoT, retailing and e-commerce, logistics, insurance, and securities, etc.

    3. Storage Classification

    The underlying storage of TencentDB for MySQL supports local SSD disks, SSD cloud disks, Enhanced SSD cloud disks, and Tremendous SSD cloud disks.
    Performance metrics
    Tremendoust SSD Cloud Disk
    Enhanced SSD Cloud Disk
    SSD
    Local SSD
    Maximum single disk capacity (GB)
    30000
    30000
    30000
    12000GB
    IOPS per Disk
    After adding extra capacity, the performance reaches up to 1,000,000.
    Additional performance overlay reaches 100,000
    26000
    150000
    Random IOPS Calculation Formula
    Benchmark performance :Random IOPS = min{4000+Capacity(GiB)×100, 50000} Additional Performance :Maximum IOPS = min{Additional Performance Value×128, 950000}
    Benchmark performance :Random IOPS = min{1800+capacity(GiB)×50, 50000}
    Additional performance :Maximum IOPS = min{Additional performance value×128, 50000} For details, see Enhanced SSD Cloud Block Storage Performance Description
    Random IOPS = min{1800+capacity(GiB)×30, 26000}
    IOPS varies with specifications, see Instance specifications
    Maximum single disk Throughput (MB/s)
    After adding extra capacity, the performance reaches up to 4000 MB/s.
    Additional performance overlay achieves 1000MB/s
    260MB/s
    -
    Throughput performance calculation formula (MB/s)
    Benchmark performance :Throughput = min{120+Capacity(GiB)×0.5, 350}
    Additional Performance :Throughput = min{Additional Performance Value×1, 3650}
    Benchmark performance :Throughput = min{120+Capacity(GiB)×0.5, 350}
    Additional performance: Throughput = min{Additional performance value×1, 650} For details, see Enhanced SSD Cloud Block Storage Performance Description
    Throughput = min{120+Capacity(GiB)×0.2, 260}
    -
    Single-lane random read and write latency (ms)
    0.1ms - 0.5ms
    0.2ms - 1ms
    0.5ms - 3ms
    Microsecond level

    4. Resource Isolation Policy

    The isolation policies for TencentDB for MySQL include Basic Type, General Type, Dedicated Type, Standard Type, and Enhanced Type.
    Resource Isolation Policy
    Description
    Basic Type
    Only single-node instances support the basic isolation policy (formerly basic edition), where there is a separation between computing and storage, with the underlying layer using cloud disk storage.
    General Type
    An instance exclusively utilizes allocated memory and disk resources while sharing CPU resources with other general instances on the same physical machine.
    Benefit from resource sharing, bringing higher cost-effectiveness and minor CPU resource reutilization.
    Dedicated Type
    An instance has dedicated CPU (with core binding), memory, and disk resources. It promises long-term performance stability and remains unaffected by the behavior of other instances on the physical machine.
    The peak configuration of the dedicated type is to occupy a physical machine alone, taking full control over all its resources.
    Standard Type
    Exclusive allocation of CPU and memory ensures long-term stable performance.
    A decoupled architecture of computing and storage offers flexible configuration options.
    Enhanced Type
    Enhanced frequency CPU cores deliver optimal performance.
    Exclusive allocation of CPU and memory ensures long-term stable performance.
    A decoupled architecture of computing and storage offers flexible configuration options.
    Supports Tremendous SSD cloud disk, providing stable and reliable performance.

    Product Selection

    You can follow the following steps to select an instance:
    1. Selecting Database Storage Engine If full transaction support and superior read-write concurrency are required, we recommend selecting InnoDB. If you want to cut down on storage costs, RocksDB would be the preferable choice. It provides comparable performance to InnoDB with only 50% or even less of the storage space.
    2. Selecting Instance Architecture Generally, a two-node architecture employing a classic primary-standby high-availability architecture is recommended. It is appropriate for industries like Internet, IoT, retailing e-commerce, logistics, gaming, or medium to large corporations. If your operations demand a financial-grade reliability, security, high availability, and disaster recovery abilities typical for industries such as finance, securities, insurance, or core database of large corporations, we recommend a three-node architecture. For personal learning, miniature websites, non-core small-scale enterprise systems, or the development and testing environments of large and medium-sized corporations, a single-node architecture would be a better choice.
    3. Selecting Storage Type The current options for storage type include local SSD disks for instances using a two-node or three-node architecture. The options for single-node architecture instances are SSD CBS and advanced SSD CBS.In the Cluster Edition architecture, instances support the selection of storage types, including Tremendous SSD cloud disks, Enhanced SSD cloud disks, and SSD cloud disks. The cloud disk architecture single-node instances, based on a cloud-native architecture, are suitable for testing, development, personal learning and other scenarios. They support up to 30 TB storage space. The storage size has an impact on IOPS. For the performance metrics of different storage types, please refer to Storage Type.
    4. Selecting Resource Isolation Policy and Instance Specifications The single-node architecture supports the basic isolation policy, while two-node and three-node architectures support both general and dedicated isolation policies. The Cluster Edition architecture supports standard and enhanced isolation policies. The parameters of the instance specifications include vCPUs, memory, maximum IOPS, and maximum storage capacity. You may select the appropriate specifications based on your business needs.
    Note:
    For details about all available models and selection options, please see Purchase Methods.

    Related Documents

    
    Contact Us

    Contact our sales team or business advisors to help your business.

    Technical Support

    Open a ticket if you're looking for further assistance. Our Ticket is 7x24 avaliable.

    7x24 Phone Support