Hi, I'm doing simple tests with lsof on data catalog with bash script: #!/bin/bash for i in {0..2000} do psql -U postgres -c '*BEGIN; select pg_sleep(30); COMMIT*'& done and i measure number of open files and what files are affected by specific command. Lsof has shown me that the only file that was open during this test was: data/base/13328/2601, which is pg_catalog table pg_am. Why postgres opens a table that stores information about relation (index) access methods, while none index evidently is in use? -- View this message in context: http://postgresql.nabble.com/pg-am-access-in-simple-transaction-tp5931974.html Sent from the PostgreSQL - general mailing list archive at Nabble.com. -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general