"Mauricio Breternitz" <mbjsql@hotmail.com> writes:
> My concern is whether that is enough to maintain consistency
> in the buffer cache
No, it isn't --- for one thing, WriteBuffer wouldn't cause other
backends to update their copies of the page. At the very least you'd
need to synchronize where the LockBuffer calls are, not where
WriteBuffer is called.
I really question whether you want to do anything like this at all.
Seems like accessing the shared buffers right where they are will be
fastest; your approach will entail a huge amount of extra data copying.
Considering that a backend doesn't normally touch every byte on a page
that it accesses, I wouldn't be surprised if full-page copying would
net out to being more shared-memory traffic, rather than less.
regards, tom lane
