OceanStor Dorado V6 storage systems support SSDs. You need to know the performance of SSDs when planning storage.
SSDs do not have HDD rotation latency. For I/O models with obvious access hotspots and latency-sensitive responses, SSDs have obvious performance advantages over HDDs, especially for random small I/Os that are common in many database applications. However, for bandwidth-intensive applications, SSDs provide only a slight improvement in performance than HDDs. In the tiered storage technology, SSDs are used as the high-performance tier that bears high IOPS pressure.
If the front end of the storage system is normal, check whether the disk performance reaches the upper limit. When the disk performance reaches the upper limit (disk utilization is close to 100%), the storage performance is limited by the back-end disk performance, and the IOPS and bandwidth performance cannot be improved. You can view the disk usage on DeviceManager.
To ensure disk reliability and service life, it is recommended that the disk usage be lower than 70%. If the usage of most disks is greater than 90%, you are advised to add disks to the storage pool or migrate services to disks with better performance.
