On Saturday, December 24, 2011 03:46:16 PM Tom Lane wrote:
> Simon Riggs <simon@2ndQuadrant.com> writes:
> > After the various recent discussions on list, I present what I believe
> > to be a working patch implementing 16-but checksums on all buffer
> > pages.
>
> I think locking around hint-bit-setting is likely to be unworkable from
> a performance standpoint. I also wonder whether it might not result in
> deadlocks.
Why don't you use the same tricks as the former patch and copy the buffer,
compute the checksum on that, and then write out that copy (you can even do
both at the same time). I have a hard time believing that the additional copy
is more expensive than the locking.
Andres