Windows XP and Vmware Tips

I have had few issues related to Vmware, slow hard disk in Windows XP and long boot time in Windows XP. Thought of sharing the solutions for these issues with everyone of you.

Slow Hard disk in Windows XP

You don't think your brand new computer could be running much more inefficiently than a 20 year old PC, do you? Mine did for some time, I didn't even realize it. My computer was taking lot of CPU even for mundane tasks such as copying files and the performance was getting worse. ProcExplorer showed hardware interrupts taking 70-80% of CPU.

The reason? The hard disk was running in Programmed IO mode (PIO mode) in which CPU was responsible for data transfer instead of DMA (Direct Memory Access) Controller. Right click My Computer -> properties -> Hardware -> Device Manager. Expand IDE ATA/ATAPI controllers and right click Primary IDE Channel and choose properties. Goto advanced settings and see the Current Transfer Mode. It should be Ultra DMA or NOT PIO.

If it is PIO, just goto Driver tab and click "Uninstall Driver" and reboot twice. If you would like to learn this in depth here are two good sources.

http://support.microsoft.com/kb/817472
http://winhlp.com/WxDMA.htm

Slow Boot time in Windows XP

Does your system stays long time in Windows XP Logo screen? It could be due to a corrupt program in Windows Prefetch directory, where Windows stores frequently used programs for faster fetching. Delete C:\windows\prefetch\*.pf files and reboot your computer.

Virtual machine fails to boot

I have some of my vms running on a NTFS filesystem mounted on a linux box using a ntfs-3g driver. The net effect is that the disk performance is relatively slow. Same could be said of USB 1.1 hard drives and network mounted drives. If you are running your VMs from any of these and your virtual machine fails to boot, try adding the following line to your *.vmx configuration file.

mainMem.useNamedFile = "False"

Hope you find these tips useful.