Hi, Le 9 février 2017 10:59:53 GMT+01:00, Lazaro Garcia <lazaro3487@xxxxxxxxx> a écrit : [...] >Is there any way to tuning this behavior? The fact is that pgpool need to parse every single query going through it, guess if the query is a RO or a Rw, then decide what to do with it. Which means: - It adds a latency on every single query - pgpool itself can become a bottleneck, especially during bench with lot of small and fast queries - Pgpool handles N client connections and N*M backends connection - It tracks xact, prepared queries, etc In short, pgpool is not transparent and free of load... >De: Lazaro Garcia [mailto:lazaro3487@xxxxxxxxx] >Enviado el: miércoles, 8 de febrero de 2017 05:28 p. m. >Para: 'pgpool-general@xxxxxxxxxx'; 'pgsql-admin@xxxxxxxxxxxxxx' >Asunto: Why pgpool TPS is lowest versus postgresql direct connections? > > > >After installed Pgpool with 2 postgresql nodes with streaming >replication, I >have noticed that access directly to postgresql is more efficient than >through pgpool. > > > >I supposed that load balance could increase the transactions per second >executed because each node could receive more load, but the results >shown >below are not expected. > > > >This is the setup: > > > >Pgpool 3.6.1 whit connection pooling, streaming replication mode and >load >balancing mode. > > > >2 PostgreSQL server 9.6.1 whit streaming replication. > > > >For the tests I used sysbench and pgbench. > > > >The results of sysbench: > > > > >Concurrent Users > >1 > >20 > >50 > >100 > > >PostgreSQL (TPS) Direct > >1166 > >20936 > >25743 > >27344 > > >Pgpool (TPS) > >2240 > >7628 > >7013 > >6135 > > > > > >The results of pgbench > > > > >1 > >20 > >50 > >100 > > >PostgreSQL (TPS) Direct > >1403 > >6805 > >6194 > >5726 > > >Pgpool (TPS) > >511 > >5430 > >5528 > >4705 > > > > > >As you can see in both cases even with load balance, the total >transactions >per second are lower. > > > >Is this the expected behavior. Is there any way to allow more TPS when >pgpool is used? > > > >There are other publications with similar results: > > > >https://www.os3.nl/_media/2011-2012/courses/lia/rory_breuk_gerrie_veerman_-_ >report.pdf (page 28) > >http://www.mail-archive.com/pgpool-general@xxxxxxxxxxxxx/msg03326.html > > > > > >Regards -- Envoyé de mon appareil Android avec K-9 Mail. Veuillez excuser ma brièveté. -- Sent via pgsql-admin mailing list (pgsql-admin@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-admin
