On 11/30/22 20:51, Ron wrote:
ZFS will yes be slower than a raw disk (but that’s not an option for Pg anyway), and may or may not be faster than a different filesystem on a HW RAID volume or storage array volume. It absolutely takes more care/clue/tuning to get Pg write performance on ZFS, and ZFS does duplicate some of Pg’s resiliency so there is duplicate work going on.
Ron, if this raw device reference is about ASM, Oracle has a file
system on top of ASM, called ACFS, and I have been able to run
PostgreSQL on top of ACFS. The reason to do that is redundancy.
ASM/ACFS with PostgreSQL behaves similarly to Veritas Cluster,
when one Postgres cluster goes down, the other one is started. And
you don't have to pay for it, unless you start using storage
snapshots. That ACFS feature requires a commercial license.
-- Mladen Gogala Database Consultant Tel: (347) 321-1217 https://dbwhisperer.wordpress.com
