[Simh] Excess IOs running SIMH on Windows/XP

[Villy Madsen]

Valid point Paul
 
as long as you make sure that you don't use an extension on the list..
 
Easier just to turn it off 
 
But then the problem was figuring out what the problem was,
 
Villy

  _____  

From: simh-bounces at trailing-edge.com [mailto:simh-bounces at trailing-edge.com] On
Behalf Of Paul Hardy 2
Sent: Sunday, January 27, 2008 14:21
To: simh at trailing-edge.com
Subject: Re: [Simh] Excess IOs running SIMH on Windows/XP


It strikes me that a quicker and safer way to solve this would be not to use
*.dsk as the file extension for simh virtual disks on Windows, but instead
rename them as *.vdisk or similar. I plan to rename mine, and just change
VAX.INI to reference the new names.
 

-- 
Paul  Hardy
Email: paul at the hardy.demon.co.uk domain


----- Original Message ----- 
From: Brian  <mailto:brian at quarterbyte.com> Knittel 
To: simh at trailing-edge.com 
Sent: Friday, January 25, 2008 6:28 PM
Subject: Re: [Simh] Excess IOs running SIMH on Windows/XP

If someone wants to do an experiment, here is the information 
I have about the way to change the list of files covered 
by System Restore on Windows XP and Vista. 


On XP, there is "super-hidden" file named 
\windows\system32\restore\filelist.xml that specifies 
the file types and directories covered by System Restore. 
This file has the System, Hidden and Readonly attributes 
set. Log on as an Administrator and in a Command Prompt 
window type: 


   cd \windows\system32\restore 
   attrib -s -h -r filelist.xml 
   notepad filelist.xml 


This file has elements named <FILES> and <DIRECTORIES> 
and <EXTENSIONS>, with <Include> and <Exclude> elements within 
each. Not too hard to decypher. I don't know what extension 
you're using for your VAX disk images, but I see that DSK 
is listed in the <EXTENSIONS><Include> section. 


So -- if someone wants to experiment with this on XP, 
how about excluding the directory that contains 
your VAX disk images by adding a new <REC> entry 
inside <DIRECTORIES><Include>, in the form 
<REC>c:\path\to\vax\files</REC>. Also, be sure that 
System Protect is ON on the drive that holds 
your VAX disk images. 


Restart XP, log on as an Administrator, and request that 
it take a System Restore point by following these steps: 


1. Click Start, All Programs, Accessories, System Tools, 
   System Restore. 


2. Select Create a Restore Point and click Next 


3. Enter a description e.g. "Test after excluding VAX directory" 


4. Click Create 


Wait until disk activity ceases, then try running the 
VAX simulator. Does the disk activity problem occur? 


On Vista, System Restore, and on Business/Enterprise/Ultimate, 
the Complate PC Backup and "Previous Files" features, are handled 
by the Volume Shadow Copy service, so entire files are not 
copied all at once as on XP. Original versions of changed blocks 
are archived one at a time. 


Tecnnically, you can't guarantee exclusion from coverage 
by System Restore on Vista, since the backup occurs at the 
block level, below the file system. But you can "advise" it to 
try to avoid specified files. It's done in the registry under 
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\BackupRestore\FilesNotToSnap
shot 


There is probably no no compelling reason to try to exclude the 
VAX disk images from coverage under Vista. Only changed blocks are 
copied so it won't consume much time or space. I suppose if 
you ever restore the disks from virtual tape, you'd be doing 
double the work there. 


I'd be interested in knowing if this does turn out to 
be the answer to the VAX disk activity issue. 


Regards 
Brian 






Brian 
 



  _____  




_______________________________________________
Simh mailing list
Simh at trailing-edge.com
http://mailman.trailing-edge.com/mailman/listinfo/simh

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.trailing-edge.com/pipermail/simh/attachments/20080127/ff4d2b3b/attachment-0003.html>