On a Windows Server 2008 R2-based computer, it usually takes you lots of time to troubleshoot slow performance or unresponsiveness issues that occur when you perform disk I/O operations.
The most common cause of I/O latency issues is faulty or underperforming drivers. These latency issues occur specifically with disk or filter drivers. Disk drivers typically are associated with third-party Storage Area Network (SAN) products. Filter drivers typically are associated with antivirus, security, or encryption products.