Abstract: With the prevalence of cloud computing, users’ requirements for cloud databases are becoming increasingly complex. The current write-once-read-many cloud database system, based on shared storage, cannot support the dynamic expansion of write performance. Multiple master nodes provide write services simultaneously, which can cause cross-node read and write conflicts, eventually leading to inconsistencies in the cache of multiple master nodes. For this problem, optimistic conflict detection based on globally ordered transaction logs can detect cross-node transaction conflicts, roll back conflicting transactions, and maintain the isolation level and consistency of the overall system. By broadcasting and replaying the global orderly transaction log, moreover, the modification of the master node can be synchronized to the remaining nodes to ensure the independent service capability of each individual node. This multi-master cache consistency solution based on global transaction logs is implemented on the open source database MySQL, and the impact on system performance is verified through experiments.

Key words: cloud database, multi-master cache, transaction log