On Tue, Nov 8, 2011 at 1:50 PM, Robert Haas <robertmh...@gmail.com> wrote:
> But there's an efficiency argument against doing it that way. First, > if we release the pin then we'll have to reacquire the buffer, which > means taking and releasing a BufMappingLock, the buffer header > spinlock, and the buffer content lock. Second, instead of returning a > pointer to the data in the page, we'll have to copy the data out of > the buffer before releasing the pin. The only way I can see this working is to optimise this in the planner, so that when we have a nested loop within a loop, we avoid having the row on the outer loop pinned while we perform the inner loop. -- Simon Riggs http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
