I am reading about where PostgreSQL stores its data it needs to offer me its service (here: http://www.postgresql.org/docs/8.4/static/storage-file-layout.html )
As it is writen there PostgreSQL's data and storing seems to work on top of the respective filesystem in which I store the
PGDATA folder. In this folder again the data is stored in a set of individual files (i.e. also files per database).
Question: While I can get along with such an "in-filesystem-setup",
I wonder if it is possible to setup PostgreSQL to use directly a block device (like /dev/sda) on for POSIX systems for data storage?
I would think that this would offer some advantages:
- the blocksize configuration and optimization to fit database to filesystem needs no longer be undertagen
- overhead in the filesystem can be avoided
- backup can be simpler
If not for PostgreSQL are there database applications known that do not rely on keeping its data as files filesystem, but use block devices directly?