Em qua., 25 de mai. de 2022 às 08:26, Ranier Vilela <ranier...@gmail.com> escreveu:
> Em qua., 25 de mai. de 2022 às 07:13, Tomas Vondra < > tomas.von...@enterprisedb.com> escreveu: > >> >> >> On 5/25/22 11:07, Ranier Vilela wrote: >> > Em qua., 25 de mai. de 2022 às 00:46, Andres Freund <and...@anarazel.de >> > <mailto:and...@anarazel.de>> escreveu: >> > >> > Hi Andres, thank you for taking a look. >> > >> > >> > On 2022-05-24 12:28:20 -0300, Ranier Vilela wrote: >> > > Linux Ubuntu 64 bits (gcc 9.4) >> > > ./pgbench -M prepared -c $conns -j $conns -S -n -U postgres >> > > >> > > conns tps head tps patched >> > > 1 2918.004085 3190.810466 >> > > 10 12262.415696 17199.862401 >> > > 50 13656.724571 18278.194114 >> > > 80 14338.202348 17955.336101 >> > > 90 16597.510373 18269.660184 >> > > 100 17706.775793 18349.650150 >> > > 200 16877.067441 17881.250615 >> > > 300 16942.260775 17181.441752 >> > > 400 16794.514911 17124.533892 >> > > 500 16598.502151 17181.244953 >> > > 600 16717.935001 16961.130742 >> > > 700 16651.204834 16959.172005 >> > > 800 16467.546583 16834.591719 >> > > 900 16588.241149 16693.902459 >> > > 1000 16564.985265 16936.952195 >> > >> > 17-18k tps is pretty low for pgbench -S. For a shared_buffers >> > resident run, I >> > can get 40k in a single connection in an optimized build. If you're >> > testing a >> > workload >> shared_buffers, GetSnapshotData() isn't the bottleneck. >> And >> > testing an assert build isn't a meaningful exercise either, unless >> > you have >> > way way higher gains (i.e. stuff like turning O(n^2) into O(n)). >> > >> > Thanks for sharing these hits. >> > Yes, their 17-18k tps are disappointing. >> > >> > >> > What pgbench scale is this and are you using an optimized build? >> > >> > Yes this optimized build. >> > CFLAGS='-Wall -Wmissing-prototypes -Wpointer-arith >> > -Wdeclaration-after-statement -Werror=vla -Wendif-labels >> > -Wmissing-format-attribute -Wimplicit-fallthrough=3 -Wcast-function-type >> > -Wformat-security -fno-strict-aliasing -fwrapv >> > -fexcess-precision=standard -Wno-format-truncation >> > -Wno-stringop-truncation -O2' >> > from config.log >> > >> >> That can still be assert-enabled build. We need to see configure flags. >> > ./configure > Attached the config.log (compressed) > > >> >> > pgbench was initialized with: >> > pgbench -i -p 5432 -d postgres >> > >> > pgbench -M prepared -c 100 -j 100 -S -n -U postgres >> >> You're not specifying duration/number of transactions to execute. So >> it's using just 10 transactions per client, which is bound to give you >> bogus results due to not having anything in relcache etc. Use -T 60 or >> something like that. >> > Ok, I will try with -T 60. > Here the results with -T 60: Linux Ubuntu 64 bits shared_buffers = 128MB ./pgbench -M prepared -c $conns -j $conns -T 60 -S -n -U postgres pgbench (15beta1) transaction type: <builtin: select only> scaling factor: 1 query mode: prepared number of clients: 100 number of threads: 100 maximum number of tries: 1 duration: 60 s conns tps head tps patched 1 17126.326108 17792.414234 10 82068.123383 82468.334836 50 73808.731404 74678.839428 80 73290.191713 73116.553986 90 67558.483043 68384.906949 100 65960.982801 66997.793777 200 62216.011998 62870.243385 300 62924.225658 62796.157548 400 62278.099704 63129.555135 500 63257.930870 62188.825044 600 61479.890611 61517.913967 700 61139.354053 61327.898847 800 60833.663791 61517.913967 900 61305.129642 61248.336593 1000 60990.918719 61041.670996 Linux Ubuntu 64 bits shared_buffers = 2048MB ./pgbench -M prepared -c $conns -j $conns -S -n -U postgres pgbench (15beta1) transaction type: <builtin: select only> scaling factor: 1 query mode: prepared number of clients: 100 number of threads: 100 maximum number of tries: 1 number of transactions per client: 10 conns tps head tps patched 1 2918.004085 3211.303789 10 12262.415696 15540.015540 50 13656.724571 16701.182444 80 14338.202348 16628.559551 90 16597.510373 16835.016835 100 17706.775793 16607.433487 200 16877.067441 16426.969799 300 16942.260775 16319.780662 400 16794.514911 16155.023607 500 16598.502151 16051.106724 600 16717.935001 16007.171213 700 16651.204834 16004.353184 800 16467.546583 16834.591719 900 16588.241149 16693.902459 1000 16564.985265 16936.952195 Linux Ubuntu 64 bits shared_buffers = 2048MB ./pgbench -M prepared -c $conns -j $conns -T 60 -S -n -U postgres pgbench (15beta1) transaction type: <builtin: select only> scaling factor: 1 query mode: prepared number of clients: 100 number of threads: 100 maximum number of tries: 1 duration: 60 s conns tps head tps patched 1 17174.265804 17792.414234 10 82365.634750 82468.334836 50 74593.714180 74678.839428 80 69219.756038 73116.553986 90 67419.574189 68384.906949 100 66613.771701 66997.793777 200 61739.784830 62870.243385 300 62109.691298 62796.157548 400 61630.822446 63129.555135 500 61711.019964 62755.190389 600 60620.010181 61517.913967 700 60303.317736 61688.044232 800 60451.113573 61076.666572 900 60017.327157 61256.290037 1000 60088.823434 60986.799312 regards, Ranier Vilela
