I have a DB which, among other things, stores images (as bytea, if that's interesting). It also stores users' metadata, activity logs, etc., but images currently take 500MB out of the total 600MB data.
I'm a complete newbie, but if I understand correctly PG has (at least) 2 pools of buffers, one for indexes and one for "heap" (data).
I imagine that my images 'pollute' the heap cache, making virtually nothing else cached (the cache obviously is not large enough to accommodate all the images).
Can I stop the image blocks only (I don't mind the image indexes being cached) from being cached?