Windows Server 2003 RTM
Windows Server 2003 Service Pack 1 (SP1)
Windows Server 2003 Service Pack 2 (SP2)

Best practices for optimal disk i/o on Windows Server 2003 Service Pack 2.

As more more data centers install SAN’s and NAS devices, they end up running into disk i/o bottlenecks.

From my personal experience, you get the most out (90%-99%) of the performance benefits from steps 1-9 which are hardware vendor related.  You will get at most (1%-10%) of performance gains from Step 10-14.

Here are some common issues that we have seen:

1) BIOS update

Support:  OEM hardware vendor

2) Storage driver and firmware update from the OEM hardware vendor

Support:  OEM hardware vendor

Note:  There are times that we see Administrators installing all the storage drivers under the sun on their images.  This causes slowness for disk i/o, failover of the disk resources if on a Failover Cluster configuration.

3) Storage driver and firmware update from the SAN or NAS vendor.

Support:  OEM hardware vendor

4) Update the HBA driver and firmware

Support:  OEM hardware vendor

5) HBA queue depth settings

Support:  OEM hardware vendor

6) Update the Multipathing software

Support:  OEM hardware vendor

7)  When setting up the disks, choose wisely on Raid configuration.

Raid 0 is usually the fastest.  Drawback:  No redundancy.

Raid 1+0 gives you the speed and the redundancy.  Drawback:  More disks = pricier.

Support:  OEM hardware vendor

8)  Smaller disk sizes equal better performance.  The more spindles, the less seek.

Support:  OEM hardware vendor

9)  Faster the RPM, the faster the reads/writes are.

15,000 RPM disk drives are currently the fastest.

Support:  OEM hardware vendor

10) When creating the volumes, make sure that the correct Volume Alignment (a.k.a. Sector Alignment).

929491 Disk performance may be slower than expected when you use multiple disks in Windows Server 2003, in Windows XP, and in Windows 2000

11)  When formatting the disk drives, you want to use the correct NTFS Allocation Unit Size (NTFS block size).

For example:  SQL needs a 64K cluster size.

12)  Make sure that all the kernel filter drivers are up to date.

antivirus software

backup software

quota management software

Outdated kernel filter drivers could cause the symptoms described below:

822219 Your system stops responding, you experience slow file server performance, or delays occur when you work with files that are located on a file server

923360 You may experience various problems when you work with files over the network on a Windows Server 2003-based or Windows 2000 Server-based computer

13) HKLM\System\CurrentControlSet\Control\FileSystem\

Disablelastaccess (dword) 1 (hex)

Note:  Disabled by default on Windows Server 2008 and Windows Server 2008 R2.

14) Make sure that the Microsoft binaries are up to date:





Process Monitor (ProcMon)

Fibre trace analyzer (OEM hardware vendor)