The soft limit of MintSO scheduler is too small.

[SeaRise]

Currently, the soft limit of the minTso scheduler is set at physical cores / 2, while the size of the cop task thread pool is logical cores. This means that the number of concurrently executing MPP tasks is only 1/4 of the cop task count. However, currently, TiDB disables the sending of cop tasks and only sends MPP tasks, which may result in a decrease in QPS.