Terminal server usage 100 % cpu with ms dos based application

[Francisco]

When I start my application (ms dos based) in a Terminal
Server session, the cpu usage is 100%.

I think I can control the cpu usage by variables in
autoexec.nt but I don´t know how to do.

 

[Vera Noest [MVP]]

A lot of DOS programs use excessive polling of the keyboard and monopolize
the CPU. Try TameDOS from http://www.tamedos.com/

 

[Sleurhutje]

Add a second CPU (if possible) or use a Hyper Threading CPU. This takes the
load of a single CPU. One of our customers is very persistant is using the
DOS version of an application that also exists in a Windows version.
Although it was cheaper to use the new version they invested in a new server
(Compaq ProLiant ML350 with Dual Xeon 2.2GHz HT).

They keyboardscanning is assigned to a thread on one of the CPU's, the other
thread are wit a very low load (less than 5%).

Works fine.



Jeroen.





When I start my application (ms dos based) in a Terminal
Server session, the cpu usage is 100%.

I think I can control the cpu usage by variables in
autoexec.nt but I don´t know how to do.

 

[Vera Noest [MVP]]

This doesn't scale very well ;-)
If you have 2 concurrent users, who both run the DOS-application, you end
up with both CPUs running at 100%. Imagine having 50 concurrent users
running such a DOS application....

 

[Sleurhutje]

Vera,

The high load during keyscans are all processed on the first CPU. We have a
customer that uses Exact for DOS 7 which suffers from this problem. After
adding a second CPU all clients keep working very well, even if 4 or more
users use the application. The first CPU shows a load of 100% user time and
10% kernel time, the second CPU is at about 30% user time and 5% kernel
time. Increasing the number of clients that start this application doesn't
change these figures anymore.

All other cleints can work well without any remarkable performance impact
(they don't work that hard probably).


Jeroen.