One significant change in IBM i 7.2 is the modernization of storage tiering in the BRMS migration function. In prior releases, the migration function in BRMS works only for library migration between auxiliary storage pools (ASPs) based on the specified policies for frequency of use. However, in IBM i 7.2 with PTF SI57831 applied, the BRMS migration function is enhanced to support the migration to independent ASPs (IASPs), migration of *LNK lists for IFS files, and migration of database files to different SSD and HDD storage tiers within the same ASP.
Similar to the IBM Storage Easy Tier function, the BRMS storage tiering function within an ASP responds to the presence of Flash or SSD drives in a storage pool that also contains hard disk drives (HDDs). Those drives can be either internal or external disk drives. However, unlike IBM Storage implementations of Easy Tier, which move small pieces of data to and from faster storage based on patterns of usage, the BRMS migration function operates at a file or library level to automatically migrate frequently accessed database files in their entirety from HDDs to Flash or SSDs, thus placing such files in a faster tier of storage, and vice versa. System administrators can also choose to move a file or a library to SSD, based on knowledge that the whole file or library will be needed in the future. This aspect can be useful for month-end or quarter-end processing by moving the necessary files, which are frequently accessed only periodically, into faster storage.
For more details on this enhancement, please read this overview.
This blog post was written by Aaron Fistler. Aaron is a member of the BRMS development team and the software developer of the function described in this article. Thanks Aaron!
This blog post was edited to fix broken links on April 15, 2020.
This blog post was originally published on IBMSystemsMag.com and is reproduced here by permission of IBM Systems Media.