Why better isolation level means better performance in MS SQL Server
- by Oleg Zhylin
When measuring performance on my query I came up with a dependency between isolation level and elapsed time that was surprising to me
READUNCOMMITTED - 409024
READCOMMITTED - 368021
REPEATABLEREAD - 358019
SERIALIZABLE - 348019
Left column is table hint, and the right column is elapsed time in microseconds…