On 30 June 2017 20:14:33 GMT+01:00, Daviramos Roussenq Fortunato <daviramosrf@gmail.com> wrote: >Hi List, > >I have a Server where a simple SQL is taking a long time to return the >results the Server settings are as follows: > >Debian GNU/Linux 7 (wheezy) >CPU: Intel(R) Xeon(R) CPU E5405 @ 2.00GHz >Mem: 16GB >HD: SSG 120 GB >Postgresql 9.2 > >postgresql.conf >shared_buffers = 1536MB >work_mem = 32MB >maintenance_work_mem = 960MB >effective_cache_size = 4864MB > >I did a test with the following SQL: > >select * from MINHATABELA > > >It took 7 minutes to return the result. > > >I did the same test on a Server: > >Windows Server 2012 Standard >CPU: Intel(R) Xeon(R) CPU E5-2450 @ 2.10GHz >Mem: 24GB >HD: HD 500 GB >Postgresql 9.2 > > >postgresql.conf Default settings that come with the installation > >The same SQL returned in 3 minutes. > >The test in both Servers were done bench. > >This table has 1888240 records whose size is 458 MB > >I believe that in both Servers the response time of this SQL is very >high, >but the main thing in LINUX Server has something very wrong, I think it >is >something in the settings. > >What can I be checking?
The query needs a full table scan, so it mainly depends on the speed of your disk. Maybe you have s bloated table. Please check reltuples and relpages from pg_class on both servers and compare.
