Stretch, moving slow in Cadence 6

Hello all,

I am using Cadence IC 6.10 with latest patches on a Dell Xeon 1900
server which has 4 GB of RAM and runs RHEL 4.x WS. The cadence install
is kept on a file server which is mounted by these servers. We
generally remote login into the server from computers on the same
network. The windows PC has 512MB GeForce800 card and I use Xmanager
or X-Win32 for starting a X session. The machine itself has 4GB of RAM
and 3Ghz processor. The resolution is set to 1920X1080. I also used
another machine with 1680X1050 resolution.

When I am doing layouts and if I click the edge of a big polygon to
stretch it or try to move the polygon, the display is very slow and
jerky. The stretching edge is not able to follow my mouse. If I move
the polygon, it is redrawn for every cursor move and is slow. It makes
doing layouts impossible. If I move the mouse to the final position,
then the edge or the polygon is drawn there after some delay. This
problem does not exists when I work on Cadence IC 5.141 version
running on the same server. The difference I noticed was that in
Cadence 6 the contents of the dragging polygon is shown however in
Cadence 5.141 only outline is shown while stretching. Can the
continuous redraw at higher resolution be causing this problem? Is the
server memory to low? It does the same thing even if nothing is
running on the server and Cadence has 3.5 GB of memory available. Can
it be a network issue? Does Cadence 6 need more bandwidth? Is there a
way to turn of this "show contents of window while dragging" feature?
I have same the issue if I log into the server using a Linux machine
instead of Windows machine.

I started a vnc session on the server and used XVNC to login and the
performance is better. I am not sure why. If I work at lower
resolutions with VNC it is also much better but not as smooth as
Cadence 5.141 is.

Any suggestions will be really helpful. I am trying to help others to
transition to new version of Cadence but this seems to be a big
roadblock.

I would be grateful for any replies.

Regards,

Vaibhav

 

Vaibhav,

The reason VNC is better performance is because when you are running the
remote display all of the drawing commands have to be sent over the network
from the server you are running the software on to the X server running on
the PC, and therefore all the drawing is network bandwidth limited.

With VNC the X server is running on the same machine as the Cadence software,
so the drawing commands do not need to go over the network, and VNC optimizes
the syncing of the graphics on the viewer running on the PC and the graphics
drawn to the X server running on the server.

Due to increased graphics capabilites in IC 6.1.X it definitely requires more
bandwidth than IC 5.1.41.

As far as the dragging behavior, I believe you can turn off "True Color Drag"
in the Options->Display... form. That's definitely available in 6.1.4 (which
I just tested).

-Pete Zakel
()

Ducharm's Axiom:
If you view your problem closely enough you will recognize
yourself as part of the problem.

 

Hi Pete

Thanks for the info! I understand what you said about VNC. I was
thinking something similar. I have 6.1.3 installed so did not have the
option on the form but I changed it using envSetVal and tested it. The
performance is much better I think. I will put that option in
my .cdsenv. But I am still surprised about the network. We have a high
speed network in our department and I am not sure what else can be
done to increase the speed. I'll keep looking for more. Any more
suggestions are welcome.

Regards,

Vaibhav

 

Hello ,

Rather than using VNC, i would recommend to use NX (No machine)
It's really faster than VNC. But you will have to install it on your
server, then create a list of users...