Thanks for the input Rick..

Re how VSS works - Doh! I see I confused myself <g> Clearly differential
backups w.r.t some nominal "full backup" in ShadowStorage wouldn't work as
the reference backup would eventually disappear (on a FIFO basis) and render
the subsequent "backups" useless.... I had a momentary vision of
"differential" backups being relative to the current systems state... pity I
didn't think a moment longer and realise that would be equally pointless -
I've acknowledged your point and amended my comments in the blog!

My Windows folder alone seems to be 9.79GB (!) (45k files in 8k folders), so
I can't help wondering how Vista works out what needs to be "copied"

"Rick Rogers" <rick@mvps.org> wrote in message
news:uvaLkkseIHA.4260@TK2MSFTNGP05.phx.gbl...[color=blue]
> FWIW
>[color=green]
>> Size of C drive in GB...................................111GB (74GB free)
>> Current Number of Restore Points...............18
>> Date of Oldest Restore Point (optional)........Feb 2, 2008
>> How old is your system (months) (optional)..14 months[/color]
>
> System Restore set to default size of 15% of drive space. List
> ShadowStorage shows 15.7GB used of 16.8 maximum space available, so a
> quick calculation shows an average point is just under 1GB.
>
> Keep in mind that if the volume approaches less than 15% free space, the
> system will actively work to maintain this by reducing alloted space for
> non-critical processes. Each point contains not only the system file
> shadows, but also those of a user's files. If you have a lot of files,
> then the corresponding restore points will be larger.
>
> From your blog:
>
> "Why should a Restore Point be much less than 2GB? Because restore points
> ought to be only differences from the current system state, and if not
> much is being installed, uninstalled, updated etc. the changes should be
> relatively small."
>
> That's not how vss works. It doesn't record only changes, that would be a
> differential backup. System Restore is more akin to a "copy" of the system
> at a point in time that can be replaced on demand. Each restore point is a
> copy unto itself, and is not reliant on any other point, so each would be
> expected to be appropriately sized.
>
> --
> Best of Luck,
>
> Rick Rogers, aka "Nutcase" - Microsoft MVP
> [url]http://mvp.support.microsoft.com/[/url]
> Windows help - [url]www.rickrogers.org[/url]
> My thoughts [url]http://rick-mvp.blogspot.com[/url]
>
> "Julian" <msforums@tiger2.notthisbit.demon.co.uk> wrote in message
> news:Oz2OaUseIHA.1208@TK2MSFTNGP05.phx.gbl...[color=green]
>> Thanks to Windows Mail for messing with the formatting... so much for the
>> "columns" - I've rearranged the text
>>
>> And if you are interested in more about what the problem to be solved is
>> see [url]http://berossus.blogspot.com/search/label/System%20Restore[/url]
>>
>>[/color]
>[/color]

--
Julian I-Do-Stuff

Some Vista stuff, but mostly just Stuff at [url]http://berossus,blogspot.com[/url]