mhg@MITRE-BEDFORD.ARPA (Mark H. Granoff) (03/16/88)
>To VAX gurus-wizards: > >I'm looking into some possibilities, and need some advice on doing the >following: > >If I turn off the bit EXE$V_DUMPBUG in the longword EXE$GL_FLAGS, does anyone >know of any non-desirable side-effects? I assume you know what that flag means. If it corresponds to the SYSGEN parameter DUMPBUG, then here's what happens when it is not set (zero): If DUMPBUG is not set, crash dumps are written into the page file on the system disk (PAGEFILE.SYS), provided there is enough room in the page file for a system crash dump. If this is desireable (i.e. what you want), then your page file has to be as large as physical memory plus 1004 pages (blocks). If a crash dump gets written into the page file, it will be lost when the system is rebooted, UNLESS the SAVEDUMP parameter is set (non zero). In this case, the space in the page file must be RELEASEd via the system dump analyzer (ANALYZE/IMAGE). I hope this helps. (You can find more info (or rather, the *official* information) in the System Dump Analyzer manual, page SDA-5). +---------------------------------------------------------------------+ | Mark H. Granoff Member of the Technical Staff | +---------------------------------------------------------------------+ | USMAIL: The MITRE Corporation | ARPAnet: mhg @ mitre-bedford.ARPA | | Burlington Rd. | UUCP : linus!mbunix!mhg | | M/S B015 |-----------------------------------| | Bedford, MA 01730 | A T & T: (617) 271 - 7506 | +--------------------------- Disclaimer ------------------------------+ |The views expressed herein are my own and do not necessarily reflect | | those of my employer. | +---------------------------------------------------------------------+
nagy%warner.hepnet@LBL.GOV (Frank J. Nagy, VAX Wizard & Guru) (03/18/88)
> If I turn off the bit EXE$V_DUMPBUG in the longword EXE$GL_FLAGS, does anyone > know of any non-desirable side-effects? My guess is no - because I'd guess that this is *exactly* what the SYSGEN parameter DUMPBUG does! = Frank J. Nagy "VAX Guru & Wizard" = Fermilab Research Division EED/Controls = HEPNET: WARNER::NAGY (43198::NAGY) or FNAL::NAGY (43009::NAGY) = BitNet: NAGY@FNAL = USnail: Fermilab POB 500 MS/220 Batavia, IL 60510
JEN@VTCS1.BITNET (03/18/88)
In a posting to INFO-VAX, MIKE@uhvax1.uh.edu writes: > >To VAX gurus-wizards: > >I'm looking into some possibilities, and need some advice on doing the >following: > >If I turn off the bit EXE$V_DUMPBUG in the longword EXE$GL_FLAGS, does anyone >know of any non-desirable side-effects? It appears that this bit is equivalent to the SYSGEN DUMPBUG parameter. A reasonable assumption is that by turning the bit off, your system won't write a dump file when it crashes (note this inclues operator requested shutdowns via SYS$SYSTEM:SHUTDOWN). A quick check of SYS$SYSTEM:SYS.MAP reveals that EXE$GL_FLAGS is defined in module SYSCOMMON and referenced in: BUGCHECK INIT PAGEFAULT PROCSTRT SYS$IMGACT To be completely sure of the side effects of your actions, you should examine the source code for each of these modules to see how (or if) they reference the EXE$V_DUMPBUG bit. However, I have a feeling that you aren't asking the right question. You state that you're looking into possibilities -- for what? If you're trying to remove your SYS$SYSTEM:SYSDUMP.DMP file, there's a much easier (and supported!) way: simply rename the file (e.g., to SYSDUMP.OLD) and reboot; you may then delete SYSDUMP.OLD. If this doesn't help then please state the problem you want to solve, not the solutions you're trying to explore. Jeff E. Nelson Virginia Polytechnic Institute and State University jen@vtcs1.bitnet