• 转mysql存储引擎memory，ndb，innodb之选择

    1

    mysql的innodb和cluster的NDB引擎都支持事务，在有共同的特性外，也有不同之处：
    以mysql cluster NDB 7.3和MySQL 5.6之InnoDB为例：
    ndb7.3基于mysql5.6，包括支持innodb1.1，因此可以在cluster里使用innodb表，但这些表不是集群的。
    MySQL Cluster NDB存储引擎用分布式, shared-nothing的架构实现，这使其和innodb有不少不同之处。比如事务、外键、表限制等，具体见下表：

    Theseare shown in the following table:

    Feature

    InnoDB1.1

    MySQLClusterNDB 7.3, MySQL Cluster NDB7.4

    MySQLServer Version

    5.6

    5.6

    InnoDBVersion

    InnoDB5.6.23

    InnoDB5.6.23

    MySQLCluster Version

    N/A

    NDB7.3.9

    StorageLimits

    64TB

    3TB

    (Practicalupper limit based on 48 data nodes with 64GB RAM each; can beincreased with disk-based data and BLOBs)

    ForeignKeys

    Yes

    Priorto MySQL Cluster NDB 7.3: No. (Ignored, as withMyISAM)

    Availablein MySQL Cluster NDB 7.3.

    Transactions

    Allstandard types

    READCOMMITTED

    MVCC

    Yes

    No

    DataCompression

    Yes

    No

    (MySQLCluster checkpoint and backup files can be compressed)

    LargeRow Support (> 14K)

    SupportedforVARBINARY,VARCHAR,BLOB,andTEXTcolumns

    SupportedforBLOBandTEXTcolumns only

    (Usingthese types to store very large amounts of data can lower MySQLCluster performance)

    ReplicationSupport

    Asynchronousand semisynchronous replication using MySQL Replication

    Automaticsynchronous replication within a MySQL Cluster.

    Asynchronousreplication between MySQL Clusters, using MySQL Replication

    Scaleoutfor Read Operations

    Yes(MySQL Replication)

    Yes(Automatic partitioning in MySQL Cluster; MySQL Replication)

    Scaleoutfor Write Operations

    Requiresapplication-level partitioning (sharding)

    Yes(Automatic partitioning in MySQL Cluster is transparent toapplications)

    HighAvailability (HA)

    Requiresadditional software

    Yes(Designed for 99.999% uptime)

    NodeFailure Recovery and Failover

    Requiresadditional software

    Automatic

    (Keyelement in MySQL Cluster architecture)

    Timefor Node Failure Recovery

    30seconds or longer

    Typically< 1 second

    Real-TimePerformance

    No

    Yes

    In-MemoryTables

    No

    Yes

    (Somedata can optionally be stored on disk; both in-memory and diskdata storage are durable)

    NoSQLAccess to Storage Engine

    Nativememcached interface in development (see the MySQL Dev ZonearticleMySQLCluster 7.2 (DMR2): NoSQL, Key/Value, Memcached)

    Yes

    MultipleAPIs, including Memcached, Node.js/JavaScript, Java, JPA, C++,and HTTP/REST

    Concurrentand Parallel Writes

    Notsupported

    Upto 48 writers, optimized for concurrent writes

    ConflictDetection and Resolution (Multiple Replication Masters)

    No

    Yes

    HashIndexes

    No

    Yes

    OnlineAddition of Nodes

    Read-onlyreplicas using MySQL Replication

    Yes(all node types)

    OnlineUpgrades

    No

    Yes

    OnlineSchema Modifications

    Yes,as part of MySQL 5.6.

    Yes.

    数据驱动型应用负载于innodb和NDB存储引擎之主要不同：

    Workload

    InnoDB

    MySQLCluster (NDB)

    High-VolumeOLTP Applications

    Yes

    Yes

    DSSApplications (data marts, analytics)

    Yes

    Limited(Join operations across OLTP datasets not exceeding 3TB in size)

    CustomApplications

    Yes

    Yes

    PackagedApplications

    Yes

    Limited(should be mostly primary key access).

    MySQLCluster NDB 7.3 supports foreign keys.

    In-NetworkTelecoms Applications (HLR, HSS, SDP)

    No

    Yes

    SessionManagement and Caching

    Yes

    Yes

    E-CommerceApplications

    Yes

    Yes

    UserProfile Management, AAA Protocol

    Yes

    Yes

    这两种存储引擎适合的应用场景

    Preferredapplication requirements forInnoDB

    Preferredapplication requirements forNDB

    • Foreignkeys

      Note

      MySQLCluster NDB 7.3 supports foreign keys.

    • Fulltable scans

    • Verylarge databases, rows, or transactions

    • Transactionsother thanREADCOMMITTED

    • Writescaling

    • 99.999%uptime

    • Onlineaddition of nodes and online schema operations

    • MultipleSQL and NoSQL APIs (seeMySQLCluster APIs: Overview and Concepts)

    • Real-timeperformance

    • Limiteduse ofBLOBcolumns

    • Foreignkeys are supported, although their use may have an impact onperformance at high throughput

    2

    如何选择memory存储引擎或mysql cluster：
    When to Use MEMORY or MySQL Cluster.
    Developers looking to deploy applications that use the MEMORY storage engine for important, highly available, or frequently updated data should consider whether MySQL Cluster is a better choice. A typical use case for the MEMORY engine involves these
    characteristics:
    • Operations involving transient, non-critical data such as session management or caching. When the MySQL server halts or restarts, the data in MEMORY tables is lost.
    • In-memory storage for fast access and low latency. Data volume can fit entirely in memory without causing the operating system to swap out virtual memory pages.
    • A read-only or read-mostly data access pattern (limited updates).

    MySQL Cluster offers the same features as the MEMORY engine with higher performance levels, and provides additional features not available with MEMORY:
    • Row-level locking and multiple-thread operation for low contention between clients.
    • Scalability even with statement mixes that include writes.
    • Optional disk-backed operation for data durability.
    • Shared-nothing architecture and multiple-host operation with no single point of failure, enabling 99.999% availability.
    • Automatic data distribution across nodes; application developers need not craft custom sharding or partitioning solutions.
    • Support for variable-length data types (including BLOB and TEXT) not supported by MEMORY.

    MEMORY存储引擎和MySQL Cluster的更多细节对比参见白皮书《Scaling Web Services with MySQL Cluster: An Alternative to the MySQL Memory Storage Engine》

    Table 15.4 MEMORYStorage Engine Features

    Storagelimits

    RAM

    Transactions

    No

    Lockinggranularity

    Table

    MVCC

    No

    Geospatialdata type support

    No

    Geospatialindexing support

    No

    B-treeindexes

    Yes

    T-treeindexes

    No

    Hashindexes

    Yes

    Full-textsearch indexes

    No

    Clusteredindexes

    No

    Datacaches

    N/A

    Indexcaches

    N/A

    Compresseddata

    No

    Encrypteddata[a]

    Yes

    Clusterdatabase support

    No

    Replicationsupport[b]

    Yes

    Foreignkey support

    No

    Backup/ point-in-time recovery[c]

    Yes

    Querycache support

    Yes

    Updatestatistics for data dictionary

    Yes

    [a]Implemented in the server (via encryption functions), ratherthan in the storage engine.

    [b]Implemented in the server, rather than in the storage engine.

    [c]Implemented in the server, rather than in the storage engine.

    3

    myisam, memory, ndb, archive, innodb存储引擎功能汇总：

    Table 15.1 StorageEngines Feature Summary

    Feature

    MyISAM

    Memory

    InnoDB

    Archive

    NDB

    Storagelimits

    256TB

    RAM

    64TB

    None

    384EB

    Transactions

    No

    No

    Yes

    No

    Yes

    Lockinggranularity

    Table

    Table

    Row

    Table

    Row

    MVCC

    No

    No

    Yes

    No

    No

    Geospatialdata type support

    Yes

    No

    Yes

    Yes

    Yes

    Geospatialindexing support

    Yes

    No

    Yes[a]

    No

    No

    B-treeindexes

    Yes

    Yes

    Yes

    No

    No

    T-treeindexes

    No

    No

    No

    No

    Yes

    Hashindexes

    No

    Yes

    No[b]

    No

    Yes

    Full-textsearch indexes

    Yes

    No

    Yes[c]

    No

    No

    Clusteredindexes

    No

    No

    Yes

    No

    No

    Datacaches

    No

    N/A

    Yes

    No

    Yes

    Indexcaches

    Yes

    N/A

    Yes

    No

    Yes

    Compresseddata

    Yes[d]

    No

    Yes[e]

    Yes

    No

    Encrypteddata[f]

    Yes

    Yes

    Yes

    Yes

    Yes

    Clusterdatabase support

    No

    No

    No

    No

    Yes

    Replicationsupport[g]

    Yes

    Yes

    Yes

    Yes

    Yes

    Foreignkey support

    No

    No

    Yes

    No

    No

    Backup/ point-in-time recovery[h]

    Yes

    Yes

    Yes

    Yes

    Yes

    Querycache support

    Yes

    Yes

    Yes

    Yes

    Yes

    Updatestatistics for data dictionary

    Yes

    Yes

    Yes

    Yes

    Yes

    [a]InnoDB support for geospatial indexing is available in MySQL5.7.5 and higher.

    [b]InnoDB utilizes hash indexes internally for its AdaptiveHash Index feature.

    [c]InnoDB support for FULLTEXT indexes is available in MySQL5.6.4 and higher.

    [d]Compressed MyISAM tables are supported only when using thecompressed row format. Tables using the compressed row formatwith MyISAM are read only.

    [e]Compressed InnoDB tables require the InnoDB Barracuda fileformat.

    [f]Implemented in the server (via encryption functions), ratherthan in the storage engine.

    [g]Implemented in the server, rather than in the storageengine.

    [h]Implemented in the server, rather than in the storageengine.

    要选mysql cluster要根据ndb存储引擎的特征和应用场景做详细测试，安装简测见我的博文《centos65安装简测mysql cluster 7.3.7》http://blog.csdn.net/beiigang/article/details/43485585

    参考

    http://dev.mysql.com/doc/refman/5.6/en/mysql-cluster.html

    ----------------- 

    转载请著明出处：
    blog.csdn.net/beiigang
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  • 原文地址：https://www.cnblogs.com/Yongzhouunknown/p/4812149.html
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