m1jjh00@fed.frb.gov (Jeffrey J. Hallman) (10/19/89)
I think I saw a discussion of this before, could someone please email it to me or repost it? The situation: Four X terminals and about a dozen 3/60's pretending to be X terminals (the server runs on the 3/60, but the window manager and clients run on the host) are all running various clients on a Solbourne. This is meant to see how well our network and the Solbourne handle the load. (We're trying to decide whether or not to buy X terminals.) The problem: Even before very many windows have been opened, we see output from one of my processes appearing in somebody else's xterm window. My process was started with a command like xterm -e Xsplus & fired from a menu button by twm. After many windows have been opened by several users, the host starts to refuse further connections, saying something about not having any ptys available. My dim recollection of a previous discussion in this group is that what's happening is this: the host OS has a limited number of ptys (psuedo-terminals ?) available, which are recycled when the OS thinks a process no longer needs them. The OS incorrectly assumes that my process (xterm -e Xsplus &) is not doing any terminal I/O, becuase it is running in the background. So it gives the port to another process (the new xterm), my process writes to the screen, and voila! telepathic terminals. Is this right, or am I just confused? Is there an easy fix, or even a kludge? Is this an OS bug (or a feature :( ) that will be fixed? Jeff Hallman, Stop 71 USENET uunet!fed!m1jjh00 Division of Monetary Affairs INTERNET jhallman@fed.frb.gov Federal Reserve Board PHONE (202) 452-3424 Washington, DC 20551 <-- <-- Snail Mail