Hello everyone, after the suggestion from this mailing list, I have installed pgbouncer at my CentOS 5.6 / 64 bit server and activated its transaction mode: [databases] pref = host=/tmp user=pref password=XXX dbname=pref [pgbouncer] logfile = /var/log/pgbouncer.log pidfile = /var/run/pgbouncer/pgbouncer.pid ;listen_addr = 127.0.0.1 listen_port = 6432 unix_socket_dir = /tmp auth_type = md5 auth_file = /var/lib/pgsql/data/global/pg_auth pool_mode = transaction server_check_delay = 10 max_client_conn = 200 default_pool_size = 20 log_connections = 0 log_disconnections = 0 log_pooler_errors = 1 Now the server stopped crashing even at peak times and "pg_top -I" only shows few simultaneous commands active: last pid: 13476; load avg: 4.03, 4.02, 4.29; up 2+22:57:32 19:37:05 16 processes: 3 running, 13 sleeping CPU states: 67.8% user, 0.0% nice, 0.7% system, 27.0% idle, 4.5% iowait Memory: 3363M used, 561M free, 374M buffers, 2377M cached Swap: 7812M free PID USERNAME PRI NICE SIZE RES STATE TIME WCPU CPU COMMAND 13018 postgres 20 0 1173M 179M run 4:08 11.39% 99.99% postgres: pref pref [local] SELECT 13144 postgres 18 0 1172M 179M run 3:38 6.11% 84.15% postgres: pref pref [local] SELECT 1636 postgres 16 0 1170M 152M run 186:34 4.67% 20.79% postgres: pref pref [local] SELECT 12761 postgres 16 0 1173M 180M sleep 3:16 20.22% 5.94% postgres: pref pref [local] idle And in the /var/log/pgbouncer.log shows: 2011-06-19 19:28:05.772 3031 LOG Stats: 29 req/s, in 4087 b/s, out 116615 b/s,query 106024 us 2011-06-19 19:29:05.772 3031 LOG Stats: 29 req/s, in 3665 b/s, out 39510 b/s,query 71303 us 2011-06-19 19:30:05.772 3031 LOG Stats: 32 req/s, in 4318 b/s, out 90909 b/s,query 115946 us 2011-06-19 19:31:05.773 3031 LOG Stats: 33 req/s, in 4686 b/s, out 79397 b/s,query 84436 us 2011-06-19 19:32:05.774 3031 LOG Stats: 31 req/s, in 4478 b/s, out 108103 b/s,query 104060 us But I have a new (not so bad problem) - My php script displaying player stats: http://preferans.de/user.php?id=OK493430777441 will sometimes exit with the PDO error: SQLSTATE[26000]: Invalid sql statement name: 7 ERROR: prepared statement "pdo_stmt_00000016" does not exist When I reload it, it works ok. The SQL statements called by the script are: try { # enable persistent connections and throw exception on any errors $options = array(PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION, PDO::ATTR_PERSISTENT => true); $db = new PDO('pgsql:host=' . DBHOST . ' port=6432; dbname=' . DBNAME, DBUSER, DBPASS, $options); $sth = $db->prepare(' select first_name, city, avatar, login > logout as online from pref_users where id=? '); $sth->execute(array($id)); and so on - a dozen SELECT statements. I wonder, if this "prepared statement not found" problem is caused by transaction mode of pgbouncer and if there is a way to workaround that? And I can't switch to pgbouncer session mode, because it will hang at peak time - tried that already. Thank you Alex P.S. Here again my specs: pgbouncer-1.3.4-1.rhel5 postgresql-libs-8.4.8-1PGDG.rhel5 compat-postgresql-libs-4-1PGDG.rhel5 postgresql-8.4.8-1PGDG.rhel5 postgresql-server-8.4.8-1PGDG.rhel5 postgresql-devel-8.4.8-1PGDG.rhel5 php53-pgsql-5.3.3-1.el5_6.1 php53-pdo-5.3.3-1.el5_6.1 php53-5.3.3-1.el5_6.1 I have 4GB RAM and postgresql.conf contains: max_connections = 50 shared_buffers = 1024MB #listen_addresses = 'localhost' (i.e. unix socket only) -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general