[Simh] Excess IOs running SIMH on Windows/XP

[Brian Knittel]

Oh my goodness. Is the extension of the disk image file
file one of the extensions monitored by System Restore?
System restore could indeed be the culprit. On XP,
when a "restore point" is made, nothing is actually backed
up at that moment. When an attempt is made to modify
a protected file later on the, entire file is copied to the 
Restore Point's folder under System Volume Information.
This is handled by a file system filter driver that
monitors file open calls.

That indeed could be the cause of the disk activity when 
the simulator is started up, which has been discussed for 
a couple of years here. The symptom is that the entire
disk image appears to be read, right?

Does this activity happen every time the sim is started, or 
just once a day more or less (e.g. after the automatic daily 
system restore point is made?).

There is a registry entry that you can use to exclude files.
If this indeed what the issue is, we can address it pretty
quickly.

Vista by the way uses volume shadow copy to perform
system restore points and "complete PC Backup" on the
business/enterprise/ultimate versions. These won't cause the 
bulk copy but will copy on a block by block basis as files are 
changed.

Brian