I installed 9.2 on our new server and am seeing something odd that doesn't happen in 8.4:
postgres=# select datname, pid, usename, query from pg_stat_activity where query != '<IDLE>'; datname | pid | usename | query ------------+-------+----------+------------------------------------------------------------------------------------ emolecules | 19249 | test | DEALLOCATE dbdpg_p18629_26 emolecules | 19250 | test | DEALLOCATE dbdpg_p18625_20 emolecules | 19251 | test | DEALLOCATE dbdpg_p18632_23 postgres | 21583 | postgres | select datname, pid, usename, query from pg_stat_activity where query != '<IDLE>'; emolecules | 19253 | test | DEALLOCATE dbdpg_p18627_18 emolecules | 19320 | test | DEALLOCATE dbdpg_p18640_7 emolecules | 19271 | test | DEALLOCATE dbdpg_p18628_17 emolecules | 19779 | test | DEALLOCATE dbdpg_p19319_2 emolecules | 19282 | test | DEALLOCATE dbdpg_p18626_12 emolecules | 19321 | test | DEALLOCATE dbdpg_p19283_9
There are indeed nine Postgres backends running. They are connected to nine "fastcgi" Apache processes that sit there and wait for low-overhead requests.
What are these DEALLOCATE requests, and why do they just sit there and never finish?