Expansion method for supporting non-halt of multi-hash map database cluster system

Abstract

The invention provides an expansion method for supporting non-halt of a multi-hash map database cluster system. The expansion method comprises the following steps: S1, binding all original tables in a cluster onto an existing hash map which is named old hash map; S2, during cluster expansion, executing a command for generating a new hash map, generating the new hash map through a cluster, and setting the hash map as a current hash map; S3, automatically binding tables which are newly created after cluster expansion onto the current hash map; S4, participating into operation with new tables after performing dynamic data redistribution according to the current hash map, wherein in any operation on the original tables and the new tables, the current hash map is taken as a hash map of current operation, and the original hash characteristics of old tables based on an old hash map are lost; S5, migrating a part of data onto a new node, and binding the tables onto the current hash map after the completion of migration. Through the design, performance attenuation is avoided, and natural data transition is realized.

Description

technical field

[0001] The invention relates to the field of distributed databases, in particular to a capacity expansion method that supports multi-hash map database cluster systems without stopping. Background technique

[0002] In the customer's business scenario, when the current cluster cannot meet the user's business needs and needs to be expanded, the expansion of the cluster needs to be completed within a given time window. The main technology of cluster expansion in the traditional sense is data migration, and the expansion process is completed by redistributing part of the data on the original cluster nodes to the newly added nodes. Depending on the size of the data, data redistribution takes hours to days, and during the expansion process, the cluster does not allow DML and DDL operations, only query operations are allowed, which brings great inconvenience to cluster users. In particular, real-time system users do not allow prolonged cluster downtime. Contents ...

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