On Sun, Apr 04, 2021 at 04:12:14PM +0530, aditya desai wrote: > Hi, > We have few select queries during which we see SHARED LOCKS and EXCLUSIVE > LOCKS on tables. Can these locks cause slowness? Is there any way to reduce > the locks? > > What must be causing ACCESS EXCLUSIVE LOCKS when the application is running > select queries? Is it AUTOVACUUM? I suggest to review all the logging settings, and consider setting: log_destination = 'stderr,csvlog' log_checkpoints = on log_lock_waits = on log_min_messages = info log_min_error_statement = notice log_temp_files = 0 log_min_duration_statement = '9sec' log_autovacuum_min_duration = '99sec' You should probably set up some way to monitor logs. We set log_destination=csvlog and import them into the DB. Then I have nagios checks for slow queries, errors, many tempfiles, etc. https://www.postgresql.org/docs/current/runtime-config-logging.html#RUNTIME-CONFIG-LOGGING-CSVLOG https://www.postgresql.org/message-id/20190206232110.GH29720@xxxxxxxxxxxxx -- Justin
