On Sat, Feb 18, 2017 at 12:33 AM, Jim Nasby <jim.na...@bluetreble.com> wrote: > On 2/15/17 1:37 PM, Ryan Murphy wrote: >> attcacheoff can only be set positive for fields preceding any varlena >> (typlen<0, but including the first such) or nullable values. I don't >> know how much faster it is with the cache; you can measure it if your >> curiosity is strong enough -- just set the first column to nullable. >> >> Thanks! Maybe I'll do some benchmarks. > > You'll probably want to do those at a C level, bypassing the executor. I > would guess that executor overhead will completely swamp the effect of the > cache in most cases.
That seems like it's kind of missing the point. If the tupleDesc cache saves so little that it's irrelevant when tested through the executor, it's not a very useful cache. I bet that's not the case, though. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
