On Wed, Nov 23, 2011 at 11:25 AM, J Ramesh Kumar <rameshj1...@gmail.com>wrote:
> Hi, > > My application is performing 1600 inserts per second and 7 updates per > second. The updates occurred only in a small table which has only 6 integer > columns. The inserts occurred in all other daily tables. My application > creates around 75 tables per day. No updates/deletes occurred in those 75 > daily tables (only inserts and drop tables if older than 40 days). Since > only inserts in the daily tables, I disabled autovacuum in the conf file > and I can see it is off stat using show command. > > *sasdb=# show "autovacuum"; > autovacuum > ------------ > off > (1 row)* > > But the autovacuum is running frequently and it impact the performance of > my system(high CPU). You can see the autovacuum in the pg_stat_activity. > * > sasdb=# select current_query from pg_stat_activity where current_query > like 'autovacuum%'; > ** current_query ** > > ------------------------------**------------------------------** > --------------------------- > autovacuum: VACUUM public.xxxxx**_17_Oct_11 (to prevent wraparound) > autovacuum: VACUUM public.**xxxxx**_17_Oct_11 (to prevent wraparound) > autovacuum: VACUUM public.**xxxxx**_17_Oct_11 (to prevent wraparound) > (3 rows) > > > * Its pretty clear, its to prevent tranx wrap-around. autovacuum_freeze_max_age (integer) Specifies the maximum age (in transactions) that a table's pg_class. relfrozenxid field can attain before a VACUUM operation is forced to prevent transaction ID wraparound within the table. Note that the system will launch autovacuum processes to prevent wraparound even when autovacuum is otherwise disabled. http://developer.postgresql.org/pgdocs/postgres/runtime-config-autovacuum.html --- Regards, Raghavendra EnterpriseDB Corporation Blog: http://raghavt.blogspot.com/ > **Why the autovacuum is running even though, I disabled ? Am I miss > anything ? > > And also please share your views on my decision about disable autovacuum > for my application. I am planning to run vacuum command daily on that small > table which has frequent updates. > > Thanks, > Ramesh >
