autovacuum freeze recommendations at table level
Hi Respected Team,
Could you please let me know that how this freeze parameters work
Update query runs on table through which data being modified daily in this
case
Total records in table is about 20lakhs
current setting for this table is
Access method: heap
if it reaches > 0.1*2000000+1000 = 2,10,000 as per the formula autovacuum
triggers
Options: fillfactor=85, autovacuum_vacuum_cost_delay=0,
autovacuum_vacuum_cost_limit=3000, parallel_workers=6,
autovacuum_vacuum_scale_factor=0.1, autovacuum_vacuum_threshold=1000,
autovacuum_freeze_max_age=20000000,
autovacuum_multixact_freeze_max_age=20000000, autovacuum_freeze_min_age=0
How autovacuum freeze parameters work.Give me some recommendations to
improve the performance better than now
Ex :ALTER TABLE table SET (
autovacuum_freeze_max_age = 20000000,(2 crores)
autovacuum_multixact_freeze_max_age = 20000000,(2 crores)
autovacuum_freeze_min_age = 0
);
Regards,
Durga Mahesh
Hi Durga
*autovacuum_freeze_max_age* specifies the maximum age (in transactions)
that a table's tuples can reach before a vacuum is forced to prevent
transaction ID wraparound. when the age of the oldest tuple in the table
exceeds this value, an autovacuum is triggered to freeze the tuples.
*Recommendation = 20000000 -> 150000000 *
*autovacuum_multixact_freeze_max_age *It is similar to above, but applies
to multi-transaction IDs (used for shared row locks). when the age of the
oldest multi-transaction ID exceeds this value, an autovacuum is triggered
to freeze the multi-transaction IDs.
*Recommendation = 20000000 -> 150000000*
*autovacuum_freeze_min_age* specifies the minimum age (in transactions)
that a tuple must reach before it is considered for freezing. Lowering this
value can cause more frequent freezing, which can increase the overhead of
autovacuum.
*Recommendation = 0 -> 50000000*
Thanks, Semab
On Sun, Aug 11, 2024 at 11:12 AM Durgamahesh Manne <
maheshpostgres9@gmail.com> wrote:
Show quoted text
Hi Respected Team,
Could you please let me know that how this freeze parameters work
Update query runs on table through which data being modified daily in
this case
Total records in table is about 20lakhs
current setting for this table is
Access method: heap
if it reaches > 0.1*2000000+1000 = 2,10,000 as per the formula autovacuum
triggers
Options: fillfactor=85, autovacuum_vacuum_cost_delay=0,
autovacuum_vacuum_cost_limit=3000, parallel_workers=6,
autovacuum_vacuum_scale_factor=0.1, autovacuum_vacuum_threshold=1000,
autovacuum_freeze_max_age=20000000,
autovacuum_multixact_freeze_max_age=20000000, autovacuum_freeze_min_age=0How autovacuum freeze parameters work.Give me some recommendations to
improve the performance better than now
Ex :ALTER TABLE table SET (
autovacuum_freeze_max_age = 20000000,(2 crores)
autovacuum_multixact_freeze_max_age = 20000000,(2 crores)
autovacuum_freeze_min_age = 0
);
Regards,
Durga Mahesh
Hi Semab
ALTER TABLE table SET (
autovacuum_freeze_max_age = 60000000,(6 crores)
autovacuum_multixact_freeze_max_age = 60000000,(6 crores)
autovacuum_freeze_min_age = 0
);
I set this but autovacuum to prevent wraparound runs for every 10 minutes
on the table being modified in this case
How to minimize the impact of this ?
There is no option to set naptime at table level
I could see total records around 40 lakhs that are being modified
Toast considers large objects but I use parameters without toast.
Regards,
Durga Mahesh Manne
On Mon, Aug 12, 2024 at 10:07 PM semab tariq <semabtariq1@gmail.com> wrote:
Show quoted text
Hi Durga
*autovacuum_freeze_max_age* specifies the maximum age (in transactions)
that a table's tuples can reach before a vacuum is forced to prevent
transaction ID wraparound. when the age of the oldest tuple in the table
exceeds this value, an autovacuum is triggered to freeze the tuples.
*Recommendation = 20000000 -> 150000000 **autovacuum_multixact_freeze_max_age *It is similar to above, but applies
to multi-transaction IDs (used for shared row locks). when the age of the
oldest multi-transaction ID exceeds this value, an autovacuum is triggered
to freeze the multi-transaction IDs.
*Recommendation = 20000000 -> 150000000**autovacuum_freeze_min_age* specifies the minimum age (in transactions)
that a tuple must reach before it is considered for freezing. Lowering this
value can cause more frequent freezing, which can increase the overhead of
autovacuum.
*Recommendation = 0 -> 50000000*Thanks, Semab
On Sun, Aug 11, 2024 at 11:12 AM Durgamahesh Manne <
maheshpostgres9@gmail.com> wrote:Hi Respected Team,
Could you please let me know that how this freeze parameters work
Update query runs on table through which data being modified daily in
this case
Total records in table is about 20lakhs
current setting for this table is
Access method: heap
if it reaches > 0.1*2000000+1000 = 2,10,000 as per the formula autovacuum
triggers
Options: fillfactor=85, autovacuum_vacuum_cost_delay=0,
autovacuum_vacuum_cost_limit=3000, parallel_workers=6,
autovacuum_vacuum_scale_factor=0.1, autovacuum_vacuum_threshold=1000,
autovacuum_freeze_max_age=20000000,
autovacuum_multixact_freeze_max_age=20000000, autovacuum_freeze_min_age=0How autovacuum freeze parameters work.Give me some recommendations to
improve the performance better than now
Ex :ALTER TABLE table SET (
autovacuum_freeze_max_age = 20000000,(2 crores)
autovacuum_multixact_freeze_max_age = 20000000,(2 crores)
autovacuum_freeze_min_age = 0
);
Regards,
Durga Mahesh