Metadata describing the files in HPSS are managed by Db2 relational databases. Each relational database has tables and index files, transaction log files, archived transaction log files, and database backup files.
HPSS Metadata Best Practices:
- Store Db2 tables, index files, transaction logs, log archives, and backups on solid state storage.
- NVMe is best for IOPS and bandwidth – IOPS for fast database transactions, and bandwidth for fast backup performance.
- Use two physically-separate RAID-protected pools of storage (the minimum requirement would be two RAID-1 devices using four NVMe drives).
- Expect to allocate about 10 TB of metadata storage per billion files for each high availability copy.
- Integrate the Db2 recovery files into your site backup strategy; it is not acceptable to store the Db2 backups into HPSS.
Optional HPSS Metadata Redundancy
Db2 log shipping is used to replicate HPSS metadata to a second Db2 instance. The second instance of Db2 can be located in a different rack, room, building, or city; and is often located with the second copy of data on tape. Db2 log shipping is used to reduce downtime caused by hardware failures.