lizzymy@xxxxxxxxx (Lizzy M) writes: > I have an problem: can postgresql store its data on the raw disks now? > > I have checked the mail list and manual, but haven?t found the > answer. In some early mails, they mentioned pg didn?t support this > character. But how about now? Raw disk may reduce the risks brought by > file system, so I want to use it to store my data. No, this has not changed, and if anything, it is *less* likely to change than ever. Twenty years ago, filesystems were sufficiently fragile, unreliable and slow that DBMS vendors found it worthwhile to avoid the risks by, in effect, implementing their own filesystems as part of the DBMS. - Since then, OS vendors have found it to be in their interests to improve both the robustness and performance of their filesystems, which has substantially diminished the would-be benefits. - Compound this with the factor that implementing your own filesystem adds substantially to the complexity of managing and deploying the DBMS. The two really interesting filesystems these days are ZFS and OCFS: http://en.wikipedia.org/wiki/ZFS http://en.wikipedia.org/wiki/OCFS It seems much more useful to allow the OS vendors to improve their filesystems, which helps us, than to use raw partitions, which requires: a) Creating a portable framework for OS-agnostic access to raw partitions (because Linux != FreeBSD != Solaris != Windows NT != AIX != ...) b) Implementing our own filesystem atop raw partitions c) Implementing our own filesystem management tools (e.g. - like cp, rm, ..., since our OS tools won't work) As an aggregate, this would add an extraordinary amount of work, and with the improvements that have taken place lately, it is not evident that this would buy us *any* of: a) Improved performance b) Improved reliability Indeed, I think we could reasonably expect for there to be a significant period of time during which performance and reliability would be *degraded* by such an effort. -- let name="cbbrowne" and tld="linuxdatabases.info" in name ^ "@" ^ tld;; http://cbbrowne.com/info/rdbms.html "I'm guilty of a lot of things, but I didn't ever do that.'' -- Bill Clinton, on why he had astroturf lining the back of his pickup truck [In fact, he _DID_ do this, thus making life creepier than fiction...] -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
