Factors that impact performance

1. Appilication Architecture
2. Appilication Design
3. Transaction and Isolation Level
4. Transact-SQL Code
5. Hardware Resource
6. SQL Server Configuration
       6.1 Affinity Mask
       6.2 Lightweight Pooling
       6.3 Max work Threads
       6.4 Max Degree of Parallelism
       6.5 Min and Max Server Memory
7. Database Schema
8. Mixing log and data onto the samephysical disk
9. Sharing physical disk(s) amoung tempdb and user databases
10. Mapping heavily acessed tables onto the same physical disk