Hi, I have sen many posts on using SSDs, and iodrive <http://www.fusionio.com>in particular, to accelerate the performance of Postgresql (or other DBMS) -- e.g. this discussion<http://groups.google.co.il/group/pgsql.performance/browse_thread/thread/1d6d7434246afd97?pli=1>. I have also seen the suggestion to use RAM for the same purpose by creating a tablespace on a RAM mount point.<http://magazine.redhat.com/2007/12/12/tip-from-an-rhce-memory-storage-on-postgresql/>Granted these make most sense when the whole database cannot fit into main memory, or if we want to avoid cold DB response times (i.e waiting for the DB to "warm up" as stuff gets cached in memory).
My question is this: if we use either SSD or RAM tablespaces, I would imagine postgresql will be oblevient to this and would still cache the tablespace elemenst that are on SSD or RAM into memory - right? Is there a way to avoid that, i.e. to tell postgress NOT to cache tablespaces, or some other granularity of the DB? Thanks, -- Shaul *Dr. Shaul Dar* Email: i...@shauldar.com Web: www.shauldar.com
