On 24/09/12 22:33, Kiriakos Tsourapas wrote:
Hi,
The problem : Postgres is becoming slow, day after day, and only a full vacuum fixes the problem.
My postgresql.conf file :
======================
port = 5433 # (change requires restart)
max_connections = 100 # (change requires restart)
shared_buffers = 256MB # min 128kB. DoubleIP - Default was 32MB
synchronous_commit = off # immediate fsync at commit. DoubleIP - Default was on
effective_cache_size = 512MB # DoubleIP - Default was 128MB
log_destination = 'stderr' # Valid values are combinations of
logging_collector = on # Enable capturing of stderr and csvlog
silent_mode = on # Run server silently.
log_line_prefix = '%t %d %u ' # special values:
log_autovacuum_min_duration = 0 # -1 disables, 0 logs all actions and
autovacuum_naptime = 28800 # time between autovacuum runs. DoubleIP - default was 1min
autovacuum_vacuum_threshold = 100 # min number of row updates before
autovacuum_vacuum_scale_factor = 0.0 # fraction of table size before vacuum. DoubleIP - default was 0.2
datestyle = 'iso, mdy'
lc_messages = 'en_US.UTF-8' # locale for system error message
lc_monetary = 'en_US.UTF-8' # locale for monetary formatting
lc_numeric = 'en_US.UTF-8' # locale for number formatting
lc_time = 'en_US.UTF-8' # locale for time formatting
default_text_search_config = 'pg_catalog.english'
Given that vacuum full fixes the issue I suspect you need to have
autovacuum set wake up much sooner, not later. So autovacuum_naptime =
28800 or even = 60 (i.e the default) is possibly too long. We have
several database here where I change this setting to 10 i.e:
autovacuum_naptime = 10s
in order to avoid massive database bloat and queries that get slower and
slower...
You might want to be a bit *less* aggressive with
autovacuum_vacuum_scale_factor - I usually have this at 0.1, i.e:
autovacuum_vacuum_scale_factor = 0.1
otherwise you will be vacuuming all the time - which is usually not what
you want (not for all your tables anyway).
regards
Mark
--
Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-performance
