Does not delete pending transactions have a certain impact on performance?

The system's performance has deteriorated seriously recently, and users have found that there are many pending transactions in the Pending Transactions interface for sub-inventory.
Based on the above situation, I would like to confirm:
1. Will more pending transactions in sub-inventory affect system performance (similar to the fact that report output has been very slow recently)
2. Does the system have a solution to automatically or batch delete pending transactions?