On Tue, Mar 19, 2013 at 3:52 PM, Greg Smith <g...@2ndquadrant.com> wrote: > On 3/19/13 6:08 PM, Ants Aasma wrote: >> >> My main worry is that there is a reasonably >> large population of users out there that don't have that acceleration >> capability and will have to settle for performance overhead 4x worse >> than what you currently measured for a shared buffer swapping >> workload. > > > That would be very bad. I want to keep hammering on this part of the > implementation. If the only style of checksum that's computationally > feasible is the Fletcher one that's already been done--if that approach is > basically the most expensive one that's practical to use--I'd still consider > that a major win over doing nothing. > > While being a lazy researcher today instead of writing code, I discovered > that the PNG file format includes a CRC-32 on its data chunks, and to > support that there's a CRC32 function inside of zlib: > http://www.zlib.net/zlib_tech.html > > Is there anywhere that compiles a PostgreSQL --without-zlib that matters?
I'm confused. Postgres includes a CRC32 implementation for WAL, does it not? Are you referring to something else? I happen to remember this because I moved some things around to enable third party programs (like xlogdump) to be separately compiled: http://www.postgresql.org/message-id/e1s2xo0-0004uv...@gemulon.postgresql.org -- fdr -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
