A description of what you are trying to achieve and what results you expect. We were trying to handle our normal production load. Spuriously, postgres becomes unresponsive, though. The EXACT PostgreSQL version you are running. postgres (PostgreSQL) 9.2.6 Postgres Installation: Postgres is installed from the "PostgreSQL RPM Building Project". YUM Repo: http://yum.postgresql.org/9.2/redhat/rhel-6-x86_64/ Arch / Version: CentOS 6 - x86_64 Changes made to the settings in the postgresql.conf file: postgres=# SELECT version(); version -------------------------------------------------------------------------------------------------------------- PostgreSQL 9.2.6 on x86_64-unknown-linux-gnu, compiled by gcc (GCC) 4.4.7 20120313 (Red Hat 4.4.7-3), 64-bit (1 row) postgres=# SELECT name, current_setting(name), source postgres-# FROM pg_settings postgres-# WHERE source NOT IN ('default', 'override'); name | current_setting | source ------------------------------+--------------------------------------------------+---------------------- archive_command | rsync -a %p 172.17.10.10:/backups/pg_archives/%f | configuration file archive_mode | on | configuration file autovacuum | on | configuration file autovacuum_freeze_max_age | 1000000000 | configuration file autovacuum_max_workers | 6 | configuration file checkpoint_completion_target | 0.9 | configuration file checkpoint_segments | 256 | configuration file checkpoint_timeout | 30min | configuration file DateStyle | ISO, MDY | configuration file default_text_search_config | pg_catalog.english | configuration file effective_cache_size | 176GB | configuration file effective_io_concurrency | 10 | configuration file lc_messages | en_US.UTF-8 | configuration file lc_monetary | en_US.UTF-8 | configuration file lc_numeric | en_US.UTF-8 | configuration file lc_time | en_US.UTF-8 | configuration file listen_addresses | * | configuration file log_autovacuum_min_duration | 0 | configuration file log_checkpoints | on | configuration file log_destination | stderr | configuration file log_directory | /var/log/postgres | configuration file log_filename | postgresql-%Y-%m-%d_%H%M%S.log | configuration file log_line_prefix | %t [%p]: [%l-1] | configuration file log_lock_waits | on | configuration file log_min_duration_statement | 500ms | configuration file log_rotation_age | 1d | configuration file log_rotation_size | 0 | configuration file log_temp_files | 0 | configuration file log_truncate_on_rotation | on | configuration file logging_collector | on | configuration file maintenance_work_mem | 1GB | configuration file max_connections | 500 | configuration file max_stack_depth | 2MB | environment variable max_wal_senders | 10 | configuration file pg_stat_statements.max | 10000 | configuration file pg_stat_statements.track | all | configuration file port | 5432 | command line random_page_cost | 2 | configuration file shared_buffers | 6GB | configuration file shared_preload_libraries | pg_stat_statements | configuration file track_activities | on | configuration file track_counts | on | configuration file vacuum_freeze_min_age | 10000 | configuration file vacuum_freeze_table_age | 500000000 | configuration file wal_buffers | 4MB | configuration file wal_keep_segments | 1536 | configuration file wal_level | hot_standby | configuration file work_mem | 256MB | configuration file (48 rows) Operating system and version $ uname -a Linux db01 2.6.32-431.3.1.el6.x86_64 #1 SMP Fri Jan 3 21:39:27 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux $ cat /etc/redhat-release CentOS release 6.5 (Final) For questions about any kind of error: What you were doing when the error happened / how to cause the error. The EXACT TEXT of the error message you're getting if there is one. Copy and paste the message to the email, do not send a screenshot. What program you're using to connect to PostgreSQL The python library psycopg2 version 2.5.2 If you're using a connection pool, load balancer or application server, which one you're using and its version We are using 18 instances of pgbouncer. pgbouncer version 1.5.4 (compiled by at 2012-12-10 11:22:04) Is there anything remotely unusual in the PostgreSQL server logs? Preceeding crash: 2014-06-10 22:53:51 GMT [52621]: [1-1] ERROR: relation "pg_buffercache" does not exist at character 22 2014-06-10 22:48:28 GMT [48822]: [1-1] ERROR: syntax error at or near "pg_sleep" at character 1 2014-06-10 21:39:05 GMT [80406]: [9-1] ERROR: syntax error in tsquery: "[Route()]:*AB " 2014-06-10 21:21:23 GMT [12348]: [2-1] DETAIL: Key (user_id)=(2743403) already exists. 2014-06-10 21:21:23 GMT [12348]: [1-1] ERROR: duplicate key value violates unique constraint "google_googleprofile_user_id_key" Preceeding crash: 2014-06-10 03:33:12 GMT [18339]: [1-1] FATAL: remaining connection slots are reserved for non-replication superuser connections 2014-06-10 03:32:14 GMT [17907]: [7-1] FATAL: connection to client lost 2014-06-10 03:32:10 GMT [17964]: [1-1] FATAL: sorry, too many clients already 2014-06-10 00:58:46 GMT [38934]: [8-1] HINT: No function matches the given name and argument types. You might need to add explicit type cast CPU manufacturer and model 80 Cores vendor_id : GenuineIntel model name : Intel(R) Xeon(R) CPU E7- 4850 @ 2.00GHz cpu MHz : 1995.010 cache size : 24576 KB flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good xtopology nonstop_tsc aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr pdcm pcid dca sse4_1 sse4_2 x2apic popcnt aes lahf_lm ida arat dts tpr_shadow vnmi flexpriority ept vpid bogomips : 3990.02 Amount and size of RAM installed, eg "2GB RAM" 250 GB RAM Storage details (important for performance and corruption questions) Do you use a RAID controller? Yes. If so, what type of controller? Product Name: PERC H700 Integrated Memory: 1024 MB BBU: Present Number of DISK GROUPS: 4 Chipset: LSI Logic / Symbios Logic MegaRAID SAS 2108 [Liberator] (rev 05) Does it have a battery backed cache module? Yes. Is write-back caching enabled? Yes. Do you use software RAID? No. Is your PostgreSQL database on a SAN? No. How many hard disks are connected to the system and what types are they? 2x - Dell SSD - 46.5 GB 14x - SEAGATE ST9146853SS - 146GB 15000 RPM 64MB Cache SAS 6Gb/s How are your disks arranged for storage? Are you using RAID? Yes If so, what RAID level(s)? Virtual Drive Id Drive Type Drive Name Size RAID Type Num Disks Cache Policy ------------------------------------------------------------------------------------------------------------------ 0 Virtual Virtual Disk 0 136.1 GB 1 - Mirror 2 WriteBack, ReadAdaptive, Direct 1 CacheCade CacheCade 92.0 GB 0 - Stripe 2 WriteBack, ReadAdaptive, Direct 2 Virtual xlog 136.1 GB 1 - Mirror 2 WriteBack, ReadAdaptive, Direct 3 Virtual data 680.6 GB 1 - Mirror 10 WriteBack, ReadAdaptive, Direct What PostgreSQL data is on what disks / disk sets? Drive Name Mount Point Filesystem Postgres Use Disk Distribution ---------------------------------------------------------------------------------- Virtual Disk 0 /boot, / ext3 None 2x - 146GB 15000 SAS xlog /pg_xlog ext3 xlog 2x - 146GB 15000 SAS data /var/lib/pgsql ext3 data 10x - 146GB 15000 SAS Device Mount Point Options ---------------------------------------------------------- /dev/sda1 on /boot ext4 (rw) /dev/sdb1 on /pg_xlog ext4 (rw,noatime,nodiratime) /dev/sdc1 on /var/lib/pgsql ext4 (rw,noatime,nodiratime)