On Thu, Apr 25, 2019, 11:34 AM Martin Kováčik <kova...@redbyte.eu> wrote:
> Turning off autovacuum for the tests is a valid option and I will > definitely do this as a workaround. Each test pretty much starts with empty > schema and data for it is generated during the run and rolled back at the > end. I have a lot of tests and at the moment it is not feasible to modify > them. > > The real workload for the application is different, but there are some > cases, when we import data from remote web service in a transaction do some > work with it and then we do a commit. If there is an autovacuum during this > process I assume there will be similar problem regarding planner statistics. > Unless you are importing a huge amount of data relative to what is already there, it seems likely to be significantly less impactful than adding data to a completely empty table. The stats on a table with 0 rows and then 5000 rows is going to be night and day, while the difference between stats on 100,000 rows and 105,000 is not as impactful. Musing here. I expect others will chime in. Stats are not versioned with MVCC so it would expected that a commit in another transaction that is updating stats would influence the query plan for another transaction that is active. >
