Freeze on order entry (Win XP VM)

[dibrom]

Hi NT Support,

When I place an order in NT, NT freezes for 10 - 15 seconds then suddenly updates (no data appears to be lost). During this time, CPU drops to nearly 0% and there's no significant change to network usage. This does not happen when placing orders in simulation. The live link is through Zen-Fire.

I have NT 6.5.1000.18 observed as:
- 3 charts open ranging from tick to 15 minute
- Normal activity: CPU humming between 0 and 35%, all NT usage
- NT using 300MB Memory

My System
- Windows XP SP3 which is running inside a Virtual Machine
- 2GB and 1 CPU allocated to Windows XP VM with NT running
- Host system is a GNU/Linux system using Oracle VirtualBox as the VM
- Host system isn't doing anything else while I trade
- VT-x/AMD-V is enabled but nested paging I don't think is supported on this CPU.
- Network adapter is bridged so VM gets direct access to physical network.

I'm not expecting support for this entire set up, but I find it unusual that the system would hang when order entry occurs. Are there any tests you can recommend for me to run, or any areas that you can suggest may cause this?