If your workload is performance-centric, then it's recommended you use SSDs. By using an SSD, you can achieve significant throughput improvement by reducing the access time and write latency. To use SSDs as journals, we create multiple logical partitions on each physical SSD, such that each SSD logical partition (journal) is mapped to one OSD data partition. In this case, the OSD data partition is located on a spinning disk and has its journal on the faster SSD partition. The following diagram illustrates this configuration:
In this type of setup, you should keep in mind not to overload SSDs by storing multiple ...