[comp.windows.x] X server has too few connections - how to increase ?

mwz@kaffa.anu.oz.au (Markus Zellner) (10/02/90)

I am running a program that requires (in certain tests) 64 xterms or
XView shelltools to be open at the same time.  When I try and run this
program under the standard MIT X server, I get a message along the lines
of "too many connections".  I have RTFMed the man pages and there
doesn't seem to be any way short of recompiling the server to increase
the number of connections the X server is allowed to make.

What I want to know is whether this connection limit (which seems to be
set at 64 at the moment) can be increased, and if so how.  If it means
server recompilation, the locations of the files and what need to be
changed in them would be much appreciated (I had a look and couldn't
find anything obvious). 

--

Markus Zellner | Phd Student | mwz@anucsd.anu.oz.au

mouse@LARRY.MCRCIM.MCGILL.EDU (10/04/90)

> I am running a program that requires (in certain tests) 64 xterms or
> XView shelltools to be open at the same time.  When I try and run
> this program under the standard MIT X server, I get a message along
> the lines of "too many connections".  I have RTFMed the man pages and
> there doesn't seem to be any way short of recompiling the server to
> increase the number of connections the X server is allowed to make.

I don't think there is.  The basic problem is that it's running out of
file descriptors.

> What I want to know is whether this connection limit (which seems to
> be set at 64 at the moment) can be increased, and if so how.  If it
> means server recompilation, the locations of the files and what need
> to be changed in them would be much appreciated (I had a look and
> couldn't find anything obvious).

I remember commenting here that the server really should be capable of
forking a multiplexor process when necessary.  The only response was a
snarky message saying something like "no, the proper solution is to
upgrade to a real operating system" - meaning a release that supports
more than 30 file descriptors.  Apparently even "real" operating
systems are too limiting for some applications.

Anyway, I found the same problem (only more severe) when using the
server with xdm under Sun release 3.5 (which has a maximum of more like
30).  So I did hack in a multiplexor subprocess.  It works, but not
particularly well.  In particular, it does not know how to fork more
than one multiplexor; they are not created on demand.  It would need a
good deal of work to get it in shape for general use.

Also, there is currently a limit of (I think) 128 clients somewhere in
the dix layer; I didn't look at increasing that.

If anyone wants, I can put together the hacks I have and make it
available somewhere, but be warned that the result will definitely not
be a plug-and-play solution.

					der Mouse

			old: mcgill-vision!mouse
			new: mouse@larry.mcrcim.mcgill.edu

stripes@eng.umd.edu (Joshua Osborne) (10/16/90)

In article <mwz.654846064@kaffa>, mwz@kaffa.anu.oz.au (Markus Zellner) writes:
> I am running a program that requires (in certain tests) 64 xterms or
> XView shelltools to be open at the same time.  

Since you are talking about XView it is a good bet you are using a Sun (even
'tho XView run on lots of other things).

>When I try and run this
> program under the standard MIT X server, I get a message along the lines
> of "too many connections".  I have RTFMed the man pages and there
> doesn't seem to be any way short of recompiling the server to increase
> the number of connections the X server is allowed to make.
> 
> What I want to know is whether this connection limit (which seems to be
> set at 64 at the moment) can be increased, and if so how.

If you are running SunOS 4.1 up the soft limit on file descriptors before
you start the server (type "limit descriptors 255"), that should let you make
alot more connections...

If you are running SunOS 4.0 try it anyway.  If you are running a truely old
version of SunOS, you are SOL.  (I advise upgrading, with 4.0 you get shared
libs, and they are a *big* win).
-- 
           stripes@eng.umd.edu          "Security for Unix is like
      Josh_Osborne@Real_World,The          Mutitasking for MS-DOS"
      "The dyslexic porgramer"                  - Kevin Lockwood
"Isn't that a shell script?"                                    - D. MacKenzie
"Yeah, kinda sticks out like a sore thumb in the middle of a kernel" - K. Lidl