The system.log storage pool

By default the file system recovery log is stored in the system storage pool with file system metadata. The file system recovery log can also be placed in a dedicated pool that is called the system.log pool.

This storage pool must be created explicitly. It is highly recommended to only use storage that is as fast or even faster than what is used for the system storage pool. This recommendation is because of the high number of small synchronous data updates made to the recovery log. The block size for the system.log pool must be the same as the block size of the system pool.

The file system recovery log will only be stored in one pool.

The system.log storage pool is an optional dedicated storage pool that contains only the file system recovery logs. If you define this pool, then IBM Spectrum Scale™ uses it for all the file system recovery logs of the file system. Otherwise, the file system recovery logs are kept in the system storage pool. It is a good practice for the system.log pool to consist of storage media that is as fast as or faster than the storage media of the system storage pool. If the storage is nonvolatile, this pool can be used for the high-availability write cache (HAWC).