On Mon, Aug 18, 2014 at 04:05:07PM +0300, Heikki Linnakangas wrote: > But more to the point, I thought the consensus was to use the > highest LSN of all the blocks in the file, no? That's essentially > free to calculate (if you have to read all the data anyway), and > isn't vulnerable to collisions.
The highest-LSN approach allows you to read only the tail part of each 8k block. Assuming 512-byte storage sector sizes, you only have to read 1/8 of the file. Now, the problem is that you lose kernel prefetch, but maybe posix_fadvise() would fix that problem. -- Bruce Momjian <br...@momjian.us> http://momjian.us EnterpriseDB http://enterprisedb.com + Everyone has their own god. + -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
