Jeff Janes <jeff(dot)janes(at)gmail(dot)com> writes:
> On Thu, Dec 15, 2011 at 7:34 AM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>> This patch may or may not be useful, but this description of it is utter
>> nonsense, because we already do compute that before taking the lock.
>> Please try again to explain what you're doing?
> Currently the CRC of all the data minus the header is computed outside the lock,
> but then the header's computation is added and the CRC is finalized
> inside the lock.
Quite. AFAICS that is not optional, unless you are proposing to remove
the prev_link from the scope of the CRC, which is not exactly a
penalty-free change.
regards, tom lane