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Path: euryale.cc.adfa.oz.au!newshost.carno.net.au!harbinger.cc.monash.edu.au!msunews!news.gmi.edu!aanews.merit.net!newsxfer.itd.umich.edu!newsxfer3.itd.umich.edu!newsfeed.internetmci.com!newsfeed.direct.ca!news.he.net!cnn.nas.nasa.gov!not-for-mail From: Hugh LaMaster <lamaster@nas.nasa.gov> Newsgroups: comp.unix.bsd.freebsd.misc Subject: Mbone/vic shared memory problems (was Re: non-present SYSVSHM?) Date: Wed, 11 Jun 1997 12:34:42 -0700 Organization: NASA Ames Research Center Lines: 113 Message-ID: <339EFDD2.3359@nas.nasa.gov> References: <338C5A5E.45D397DC@ms1.hinet.net> <Pine.BSF.3.95.970605214717.20031A-100000@public.ug.cs.sunysb.edu> <5n8mak$20d@ui-gate.utell.co.uk> NNTP-Posting-Host: win144.nas.nasa.gov Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Mailer: Mozilla 3.0 (X11; U; IRIX 6.2 IP22) Xref: euryale.cc.adfa.oz.au comp.unix.bsd.freebsd.misc:42783 Brian Somers wrote: > > In article <Pine.BSF.3.95.970605214717.20031A-100000@public.ug.cs.sunysb.edu>, > xiang xia <xiax@public.ug.cs.sunysb.edu> writes: > > > > On Thu, 29 May 1997, Richard Tsai wrote: > > > >> Hi, > >> I just installed FreeBSD 2.2.1 on my machine. I found this following > >> message under X-window often: > >> cmd XF86 pid 2784 tried to use non-present SYSVSHM > >> And ppp connection would be cut afterward. > >> Does anyone know what causes this? and how to fix it? ------------ From the Manual -------------------------------------------------------- 7.5. Does FreeBSD support System V IPC primitives? Yes, FreeBSD supports System V-style IPC. This includes shared memory, messages and semaphores. You need to add the following lines to your kernel config to enable them. options SYSVSHM options "SHMMAXPGS=64" # 256Kb of sharable memory options SYSVSEM # enable for semaphores options SYSVMSG # enable for messaging Recompile and install. NOTE: You may need to increase SHMMAXPGS to some ridiculous number like 4096 (16M!) if you want to run GIMP. 256Kb is plenty for X11R6 shared memory. ---------------------------------------------------------------------------------- > > I got the same message on my PC. Is there anybody can help us? > > Thanks. > > Yes. Brian Clapper helped 6 days before your posting by pointing > at the docs :) Of course, when I had the problem, I read the manual (notice the halo glowing over my head right now?), recompiled, and everything worked fine. Sort of. Then, I went back to the manual, but couldn't find anything more than the section "7.5" above. For some reason, vic2.8 doesn't work perfectly. (It worked fine before, actually, just using X straight, but now it uses shared memory and has a problem. Yes, I can force the X server to not use shared memory, but I would like to use it, so, here is the problem.) For some reason, vic apparently wants to open a fresh shared-memory segment for each window. (Not all versions of vic do this: e.g. on Irix, I think I only see one segment when I do an ipcs, but on FreeBSD 2.2.1, I think I see one for every expanded video window). When I try to open four such windows from one process, (e.g. for Mbone users: "places around the world" when 4 or more people are broadcasting), I get the following message: shmat: too many open files Also, when I have more than about ten segments total open, (this may be a red herring) I get X Error of failed request: BadAccess (attempt to access private resource denied) And, then the vic which tried to create the next window dies completely. So, really, I have three questions: 1) How can I increase the number of possible shared memory segments available 2) How can I increase the number of files memory-mapped files a particular process may open 3) Why is vic on FreeBSD (is this an XFree86 question, or, related to some other issue?) trying to open a new segment for every video window? When I do an "ipcs" on, e.g., Irix6.2, I only see *one* segment open no matter how many video windows are going... [The environment is FreeBSD 2.2.1/XFree86 with either of the following two systems. I get exactly the same errors on both systems:] Pent 166/16 MB/SCSI/ATI Graphics Xpression/3Com3C595 PPro 200/64 MB/SCSI/#9Motion771/SMC DEC tulip 10/100 I realize that the *problem* may be between vic and XFree86, but, a brute force solution [just increase shared-memory resources] may work just fine, especially on the 64 MB system. -- Hugh LaMaster, M/S 258-5, ASCII Email: hlamaster@mail.arc.nasa.gov NASA Ames Research Center Or: lamaster@nas.nasa.gov Moffett Field, CA 94035-1000 No Junkmail: USC 18 section 2701 Phone: 415/604-1056 Disclaimer: Unofficial, personal *opinion*.