Creating many sessions on my Workstation.

[Allan Campbell]

I have a C3600 Workstation that I am trying to get more than 120 sessions on. When I get to about 115 windows the next window I try to create gives me the following message:
Xlib: connection to "host1:0.0" refused by server
Xlib: Maximum number of clients reached
Error: Can't open display: host1:0.0
Error: Couldn't find per display information

It doesn't seem to matter if I am opening multiple xterm sessions or opening remote xload windows, I get the same limit of windows that I am allowed to open. my npty, nstrpty, and nstrtel are all set to 1024. If I do ls /dev/pty*|wc -l I have 2101 listings. Is there an internal limit on the number of xwindows that can be opened?

[Joseph C. Denman]

Could be serveral things??

Check your nproc. I believe this is fomulated from max users. Max users has nothing to do with number of connections, but it is used to fomulate many of the needed parms.

Most of my doc states that max limit on sessions is memory limited, but you are not getting a memory error. I would bet you have some kernal parm set too low.

...jcd...

[Allan Campbell]

I really don't believe this to be a kernel problem since I have already upped several values. And yes the nproc is tied to maxusers, which in my case I have made 156 from the origional 128. Unless this is either an unlisted parameter or one that I am overlooking, the kernel parameter is not where it is.

[Charles Slivkoff · Accepted solution]

The X windows system has a design limitation which will limit the number of windows able to be opened to a single X server. This is due to the size of the datatype used for XID (I believe).



As an alternative, you can run multiple copies of Xvnc and open as many X clients that each will support there as well. This would effectively allow you to nest one X session within another.



VNC is available for download from here:



http://www.uk.research.att.com/vnc/index.html



Another limitiation that you may need to address is the default number of pty and pts device structures available in the kernel. Tuning of these variables would be required in addition to the creation of device files themselves. xterm/hpterm use pty devices, while dtterm uses pts devices.

[Allan Campbell]

This was very useful information. Now I know that I need to find a support package. The link that you gave me about VNC does not seem to work. I downloaded the file and untared it, but I can't get it to load. When I type the vncinstall command it looks for files that are note there in the download. I am still not working. Is there another VNC package or site?

[Allan Campbell]

I have revisited the vnc solution again and have found my problem with vnc. I needed additional files from the contributors that was not in the original download file group. It is now working fine and has solved my problem. I just need to tune it to what I need for my system. Thanks!