> > ....while we are at it -- one feature would be great for 8.4, an
> > ability to shange shared buffers size "on the fly". I expect
> > it is not trivial, but would help fine-tuning running database.
> > I think DBA would need to set maximum shared buffers size
> > along the normal setting.
>
> Shared memory segments can't be resized... There's not even a kernel
> API to do it.
Yes, but the typical way around that is to allocate additional segments.
You would want a configurable size and a limit though.
Just wanted to air this possibility, cause it seems nobody is aware
here.
It does cause all sorts of issues, but it's not like there is no way to
increase shared memory.
The dba would then reconfigure and restart at a convenient time to
reduce
the number of segments because that is typically more performant.
Andreas