Hi, On 2018-08-22 06:20:21 +0000, Noah Misch wrote: > I see jit slows the regression tests considerably:
Is this with LLVM assertions enabled or not? The differences seem bigger than what I'm observing, especially on the mips animal - which I observe uses a separately installed LLVM build. On my machine, with master, on a postgres assert build w/ non-debug llvm build: PGOPTIONS='-c jit=0' time make -Otarget -j10 -s check-world && echo success || echo f 240.37user 55.55system 2:08.17elapsed 230%CPU (0avgtext+0avgdata 66264maxresident)k PGOPTIONS='-c jit=1' time make -Otarget -j10 -s check-world && echo success || echo f 253.02user 55.77system 2:16.22elapsed 226%CPU (0avgtext+0avgdata 54756maxresident)k Using your command, on a postgres optimized build w/ non-debug llvm build: > # x86_64, non-assert, w/o llvm > $ for n in 1 2 3; do env time make -C src/bin/pg_upgrade check; done 2>&1 | > grep elapsed > 7.64user 4.24system 0:36.40elapsed 32%CPU (0avgtext+0avgdata > 36712maxresident)k > 8.09user 4.50system 0:37.71elapsed 33%CPU (0avgtext+0avgdata > 36712maxresident)k > 7.53user 4.18system 0:36.54elapsed 32%CPU (0avgtext+0avgdata > 36712maxresident)k > > # x86_64, non-assert, w/ llvm trunk > $ for n in 1 2 3; do env time make -C src/bin/pg_upgrade check; done 2>&1 | > grep elapsed > 9.58user 5.79system 0:49.61elapsed 30%CPU (0avgtext+0avgdata > 36712maxresident)k > 9.47user 5.92system 0:47.84elapsed 32%CPU (0avgtext+0avgdata > 36712maxresident)k > 9.09user 5.51system 0:47.94elapsed 30%CPU (0avgtext+0avgdata > 36712maxresident)k > andres@alap4:~/build/postgres/master-optimize/vpath$ for n in 1 2 3; do PGOPTIONS='-cjit=0' env time make -C src/bin/pg_upgrade check; done 2>&1 | grep elapsed 8.01user 3.63system 0:39.88elapsed 29%CPU (0avgtext+0avgdata 50196maxresident)k 7.96user 3.86system 0:39.70elapsed 29%CPU (0avgtext+0avgdata 50064maxresident)k 7.96user 3.80system 0:37.17elapsed 31%CPU (0avgtext+0avgdata 50148maxresident)k andres@alap4:~/build/postgres/master-optimize/vpath$ for n in 1 2 3; do PGOPTIONS='-cjit=1' env time make -C src/bin/pg_upgrade check; done 2>&1 | grep elapsed 7.88user 3.76system 0:44.98elapsed 25%CPU (0avgtext+0avgdata 50092maxresident)k 7.99user 3.72system 0:46.53elapsed 25%CPU (0avgtext+0avgdata 50036maxresident)k 7.88user 3.87system 0:45.26elapsed 25%CPU (0avgtext+0avgdata 50132maxresident)k So here the difference is smaller, but not hugely so. > # mips32el, assert, w/o llvm (buildfarm member topminnow) [1] > 28min install-check-* > 35min check-pg_upgrade > > # mips32el, assert, w/ llvm 6.0.1 [1] > 63min install-check-* > 166min check-pg_upgrade But this seems so absurdly large of a difference that I kinda think LLVM assertions (wich are really expensive and add O(N) operations in a bunch of places) might be to blame. Greetings, Andres Freund
