=?UTF-8?Q?Jo=C3=A3o_Paulo_Labegalini_de_Carvalho?= <jaopaul...@gmail.com> writes: > Good to know. I compiled from the REL_14_5 tag and did a simple experiment > to contrast building with and w/o passing --with-llvm. > I ran the TPC-C benchmark with 1 warehouse, 10 terminals, 20min of ramp-up, > and 120 of measurement time. > The number of transactions per minute was about the same with & w/o JITing. > Is this expected? Should I use a different benchmark to observe a > performance difference?
TPC-C is mostly short queries, so we aren't likely to choose to use JIT (and if we did, it'd likely be slower). You need a long query that will execute the same expressions over and over for it to make sense to compile them. Did you check whether any JIT was happening there? There are a bunch of issues in this area concerning whether our cost models are good enough to accurately predict whether JIT is a good idea. But single-row fetches and updates are basically never going to use it, nor should they. regards, tom lane