Hi, Over at -performance Mark Kirkwood tested a recent version of this (http://archives.postgresql.org/message-id/53B283F3.7020005%40catalyst.net.nz) . I thought it's interesting to add the numbers to this thread:
> Test: pgbench > Options: scale 500 > read only > Os: Ubuntu 14.04 > Pg: 9.3.4 > Pg Options: > max_connections = 200 > shared_buffers = 10GB > maintenance_work_mem = 1GB > effective_io_concurrency = 10 > wal_buffers = 32MB > checkpoint_segments = 192 > checkpoint_completion_target = 0.8 > > > Results > > Clients | 9.3 tps 32 cores | 9.3 tps 60 cores > --------+------------------+----------------- > 6 | 70400 | 71028 > 12 | 98918 | 129140 > 24 | 230345 | 240631 > 48 | 324042 | 409510 > 96 | 346929 | 120464 > 192 | 312621 | 92663 > > So we have anti scaling with 60 cores as we increase the client connections. > Ouch! A level of urgency led to trying out Andres's 'rwlock' 9.4 branch [1] > - cherry picking the last 5 commits into 9.4 branch and building a package > from that and retesting: > > Clients | 9.4 tps 60 cores (rwlock) > --------+-------------------------- > 6 | 70189 > 12 | 128894 > 24 | 233542 > 48 | 422754 > 96 | 590796 > 192 | 630672 Now, this is a bit of a skewed comparison due to 9.4 vs. 9.3 but still interesting. Greetings, Andres Freund -- Andres Freund http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers