Hi, I'm designing an appliance (think: 24/7/365/decades) in which Postgres will act as a "skin" on the sole persistent store. I.e., there is no "filesystem" visible to clients; *all* persistent (and temporary/shared) data is presented through Postgres. There are three different types of data maintained in the RDBMS: - static (firmware images, "reference" data, appliance configuration, etc) - evolving (largely static but slowly evolving) - transient (temp tables/joins, etc. built by cooperating groups of clients) As this is an appliance, cost is important -- along with availability. It's not acceptable to plan on a hardware upgrade in anything less than a decade or more) I would, ideally, like to tailor the media used for each type of (above) data. E.g., QLC SSDs for static data, SLC SSDs (or HDDs) for evolving and RAMdisks for transient. Can I do this? And, would my "expectations" for the types of accesses in each tablespace be intuitive? E.g., could I expect no/few WRITES to the tablespace with the static data if I never call for it to be explicitly updated?? (IIRC, Oracle allows a tablespace to be qualified as "READ-ONLY" and implemented on true R/O media) Or, does Postgres expect to be able to access any media however it wants (i.e., R/w), regardless of the expected access patterns of the data stored there?
