Re: WAL to RAW devices ?

[Alex Vinogradovs <AVinogradovs(at)Clearpathnet(dot)com>]

WAL segments already have their structure. Filesystem would be an
overhead, plus I meantioned access to the same storage from
multiple hosts - no filesystem mounting, synchronization and
other problems.

I figured PG folks aren't interested in adding enterprise-level storage
functionality (movable tablespaces, raw devices for tablespaces, etc),
thus I foresee the model described as the only way to achieve somewhat
decent performance in a stressed environment.


On Fri, 2007-08-31 at 19:21 -0400, Tom Lane wrote:
> Alex Vinogradovs <AVinogradovs(at)clearpathnet(dot)com> writes:
> >  The idea is to have say 2 raw devices which would be used as 2 WAL
> > segments (round-robin). RO servers will go after the one that's not used
> > at a given time with something like xlogdump utility and produce INSERT
> > statements to be then executed locally. After that import is done, a
> > command will be issued to the WO server to switch to the other segment
> > so that the cycle can repeat.
> 
> Why would you insist on these being raw devices?  Do you enjoy writing
> filesystems from scratch?
> 
> 			regards, tom lane