> Aidan Van Dyk <[EMAIL PROTECTED]> writes: >> One possibility would be to "double-buffer" the write... i.e. as you >> calculate your CRC, you're doing it on a local copy of the block, which >> you hand to the OS to write... If you're touching the whole block of >> memory to CRC it, it isn't *ridiculously* more expensive to copy the >> memory somewhere else as you do it... > > That actually seems like a really good idea. We don't have to increase > the buffer locking requirements, or make much of any change at all in > the existing logic. +1, especially if this is intended to be an > optional feature (which I agree with). > I don't think it make sense at all!!!
If you are going to double buffer, one presumes that for some non-zero period of time, the block must be locked during which it is copied. You wouldn't want it changing "mid-copy" would you? How is this any less of a hit than just calculating the checksum? -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
