Greetings,
Running `VACUUM table_name;` on a partitioned table will vacuum each partition individually, not the whole table as a single unit.
Yes, running `VACUUM table_name;` frequently on tables or partitions with heavy DML is recommended.
Regular `VACUUM` does not lock the table for reads or writes, so it won't disrupt ongoing 24/7 data operations.
"optimize autovacuum"
Yes. Adjust following parameters as per your system/environment requirement
autovacuum_max_workers,
autovacuum_freeze_max_age ,
autovacuum_vacuum_cost_delay
Following need to be first tested thoroughly in a test environment.
Recommended Alert Threshold
Alert at 50% Usage: Set the alert threshold at 1 billion used XIDs. This provides a significant buffer, giving you ample time to take corrective action before reaching the critical limit.
Calculation Rationale
Daily XID Usage: Approximately 4 billion rows per day implies high XID consumption.
Buffer Time: At 1 billion XIDs, you would still have 1 billion XIDs remaining, giving you roughly 12 hours to address the issue if your system consumes 200 million XIDs per hour.
Greetings,
In high-transaction environments like yours, it may be necessary to supplement this with manual vacuuming.
Few Recommendations
Monitor Long-Running Queries try to optimize.
Optimize Autovacuum.
Partitioning.
Adopt Vacuum Strategy after peak hours.
We have these big tables already partitioned. So does "vacuum table_name" will endup scanning whole table or just the latest/live partition which is getting loaded currently? and do you mean to say running command "vacuum table_name;" frequently on selective tables that are experiencing heavy DML ? Hope this won't lock the table anyway because the data will be written/read from these tables 24/7.
When you say, "optimize autovacuum" does it mean to set a higher value of "autovacuum_max_workers" and "autovacuum_freeze_max_age"?
Considering we have ~4 billion rows inserted daily into the table and there is limit of ~2billion to the "Maximumusedtxnids", what threshold should we set for the alerting and to have enough time at hand to fix this issue?