Hi @sakuraime ,
The data files grow in proportion to the free space of the files. I have done a test to prove that the Tempdb file is also proportionally increased in this way.
As for your "still 256MB", I want to confirm with you whether you later added the tempdb file yourself. I have a guess that "Some are 10GB" are the files that you have used before and the space has grown. Because the newly added file is the initial size.
Since tempdb will return to its initial size after restarting SQL Server, I suggest you restart SQL Server and then observe whether there is an abnormal growth.
Find the instance in the SQL Server Configuration Manager and right click on ‘Restart’.
Best regards,
Seeya
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