Hi, I have a database server that's part of a web stack and is experiencing prolonged load average spikes of up to 400+ when the db is restarted and first accessed by the other parts of the stack and has generally poor performance on even simple select queries. There are 30 DBs in total on the server coming in at 226GB. The one that's used the most is 67GB and there are another 29 that come to 159GB. I'd really appreciate it if you could review my configurations below and make any suggestions that might help alleviate the performance issues. I've been looking more into the shared buffers to the point of installing the contrib module to check what they're doing, possibly installing more RAM as the most used db @ 67GB might appreciate it, or moving the most used DB onto another set of disks, possible SSD. PostgreSQL 9.0.4 Pgbouncer 1.4.1 Linux 2.6.18-238.9.1.el5 #1 SMP Tue Apr 12 18:10:13 EDT 2011 x86_64 x86_64 x86_64 GNU/Linux CentOS release 5.6 (Final) 4 x Intel Xeon-NehalemEX E7540-HexCore [2GHz] ( 24 physical cores ) 32GB DDR3 RAM 1 x Adaptec 5805 Z SATA/SAS RAID with battery backup 4 x Seagate Cheetah ST3300657SS 300GB 15RPM SAS drives in RAID 10 1 x 500GB 7200RPM SATA disk Postgres and the OS reside on the same ex3 filesystem, whilst query and archive logging go onto the SATA disk which is also ext3. name | current_setting --------------------------------+------------------------------------------------------------------------------------------------------------------- version | PostgreSQL 9.0.4 on x86_64-unknown-linux-gnu, compiled by GCC gcc (GCC) 4.1.2 20080704 (Red Hat 4.1.2-48), 64-bit archive_command | tar jcf /disk1/db-wal/%f.tar.bz2 %p archive_mode | on autovacuum | off checkpoint_completion_target | 0.9 checkpoint_segments | 10 client_min_messages | notice effective_cache_size | 17192MB external_pid_file | /var/run/postgresql/9-main.pid fsync | off full_page_writes | on lc_collate | en_US.UTF-8 lc_ctype | en_US.UTF-8 listen_addresses | log_checkpoints | on log_destination | stderr log_directory | /disk1/pg_log log_error_verbosity | verbose log_filename | postgresql-%Y-%m-%d_%H%M%S.log log_line_prefix | %m %u %h log_min_duration_statement | 250ms log_min_error_statement | error log_min_messages | notice log_rotation_age | 1d logging_collector | on maintenance_work_mem | 32MB max_connections | 1000 max_prepared_transactions | 25 max_stack_depth | 4MB port | 6432 server_encoding | UTF8 shared_buffers | 8GB superuser_reserved_connections | 3 synchronous_commit | on temp_buffers | 5120 TimeZone | UTC unix_socket_directory | /var/run/postgresql wal_buffers | 10MB wal_level | archive wal_sync_method | fsync work_mem | 16MB Pgbouncer config [databases] * = port=6432 [pgbouncer] user=postgres pidfile = /tmp/pgbouncer.pid listen_addr = listen_port = 5432 unix_socket_dir = /var/run/postgresql auth_type = trust auth_file = /etc/pgbouncer/userlist.txt admin_users = postgres stats_users = postgres pool_mode = session server_reset_query = DISCARD ALL; server_check_query = select 1 server_check_delay = 10 server_idle_timeout = 5 server_lifetime = 0 max_client_conn = 4096 default_pool_size = 100 log_connections = 1 log_disconnections = 1 log_pooler_errors = 1 client_idle_timeout = 30 reserve_pool_size = 800 Thanks in advance Richard -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance