[Simh] VMS paging

[Bob Supnik]

The message you describe should not be occuring in normal 
startup.  The normal startup sequence is very simple:

 >>>b dua0
(BOOT/R5:0 DUA0



   2..
-DUA0
   1..0..


%SYSBOOT-I-SYSBOOT Mapping the SYSDUMP.DMP on the System Disk
%SYSBOOT-I-SYSBOOT SYSDUMP.DMP on System Disk successfully mapped
%SYSBOOT-I-SYSBOOT Mapping PAGEFILE.SYS on the System Disk
   YSBOOT-I-SYSBOOT SAVEDUMP parameter not set to protect the PAGEFILE.SYS
    OpenVMS (TM) VAX Version V7.2     Major version id = 1 Minor version id = 0

PLEASE ENTER DATE AND TIME (DD-MMM-YYYY  HH:MM)  20-JAN-2007 21:18
$!  Copyright (c) 1998 Digital Equipment Corporation.  All rights reserved.

and then off into the STARTUP.COM file.

Are you shutting down VMS correctly?  VMS, like Windows, has to be 
shutdown, you can't just simply stop the simulator.  (The command is 
simply RUN SHUTDOWN from the system account.)  If you don't,  on next 
boot you'll get the VMS equivalent of fsck or CHKDSK, which <will> 
read every piece of the disk to try to verify or restore the 
integrity of the filesystem.

/Bob Supnik

At 12:00 PM 1/20/2007, you wrote:

>Message: 1
>Date: Fri, 19 Jan 2007 17:21:22 -0000
>From: "Richard Davis" <richard_a_davis_2 at btinternet.com>
>Subject: Re: [Simh] Excessive paging of the real machine running SIMH
>         - VAX
>To: <simh at trailing-edge.com>
>Message-ID: <001601c73bee$3e950fc0$0600a8c0 at opal5>
>Content-Type: text/plain;       charset="us-ascii"
>
>HI.
>
>I've just trawled through the numerous archives and came across this thread
>(Sept 2006), it sounds remarkably like the symptoms I'm seeing on my host
>machine, it unfortunately makes the whole machine (emulated and host
>machine) grind almost to a halt.
>Using the 'Windoze task manager' to see what is going on, it seems that SIMH
>task goes page fault crazy and is doing a horrendous amount of 'I/O write
>bytes', this either occurs just after the VMS
>"WBM-I-WBMINFO Write Bitmap has successfully completed initialization." Or
>immediately the first disk mount occurs during the VMS startup, occasionally
>(only VERY occasionally) everything works just fine and the emulated
>MicroVax starts up and operates correctly.
>
>Has anyone determined exactly what is going on and any possible
>workarounds/fixes?
>
>My host machine is: 3Ghz Pentium4 with hyperthreading enabled, 3Gb RAM
>running XP sp2.
>My SIMH emulated machine: MicroVax 3900 with 64m memory, a RA72 as system
>disk and a "RAUSER=8380080" (RZ29) running VMS 7.1
>
>Thanks
>   Richard