Hello everybody, We have being doing some testing with an ISD transaction and we had some problems that we posted here. The answers we got were very kind and useful but we couldn't solve the problem. We have doing some investigations after this and we are thinking if is it possible that OS has something to do with this issue. I mean, we have two hosts, both of them with OS = Red Hat Enterprise Linux Server release 6.2 (Santiago) But when doing "select * from version()" on the postgres shell we obtain: sessions=# select * from version(); version -------------------------------------------------------------------------------------------------------------- PostgreSQL 9.1.3 on x86_64-unknown-linux-gnu, compiled by gcc (GCC) 4.4.6 20110731 (Red Hat 4.4.6-3), 64-bit (1 row) We don't understand why in here it's written "(Red Hat 4.4.6-3)". Is it possible that we have installed a postgres' version that it's not perfect for the OS? But if this is a problem, why are we obtaining a normal perform on a host and an exponential performance decrease on another? And how can we obtain a normal performance when launching the program which does the queries from another host (remote url) but when launching it in the same host we obtain this decrease on the performance? Any idea would be great! Thanks very much!!!! Useful data: name | current_setting --------------------------+-------------------------------------------------------------------------------------------- ------------------ version | PostgreSQL 9.1.3 on x86_64-unknown-linux-gnu, compiled by gcc (GCC) 4.4.6 20110731 (Red Hat 4.4.6-3), 64-bit archive_mode | off client_encoding | UTF8 fsync | on lc_collate | en_US.UTF-8 lc_ctype | en_US.UTF-8 listen_addresses | * log_directory | pg_log log_filename | postgresql-%a.log log_rotation_age | 1d log_rotation_size | 0 log_truncate_on_rotation | on logging_collector | on max_connections | 100 max_stack_depth | 2MB port | 50008 server_encoding | UTF8 shared_buffers | 32MB synchronous_commit | on TimeZone | Europe/Madrid wal_buffers | 64kB wal_sync_method | fsync (22 rows) -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance