I/O Passthrough
Overview
In balanced storage, system bottlenecks lie in HDDs. The I/O passthrough feature improves the throughput of HDDs based on how data is stored to HDDs in the Ceph cluster, thereby improving cluster performance.
Technical Principles
To ensure data reliability in the Ceph cluster, cache flush operations are performed when data is committed to drives. As a result, the write performance latency is prolonged. By bypassing such operations and allowing data to be directly persisted to drives, the data read/write efficiency can be improved.
Expected Results
In block storage where the block size is 4 KB, 16 KB, 64 KB, or 1 MB, the fio tool is used to test random mixed read/write (7:3) performance. The performance is improved by more than 15% when I/O passthrough is enabled.
Parent topic: Features