On 10/7/06, Erik Trimble <[EMAIL PROTECTED]> wrote:
Chad Leigh -- Shire.Net LLC wrote:
>>> Plus, the number of files being created under typical
>>> modern systems is at least two (and probably three or four) orders
>>> of magnitude greater. I've got 100,000 files under /usr in Solaris,
>>> and almost 1,000 under my home directory.
>>
>> wimp :-) I count 88,148 in my main home directory. I'll bet just
>> running gnome and firefox will get you in the ballpark of 1,000 :-/
>
> None (well, maybe 1 or 2) of which you edit and hence would not
> generate versions.
>
> Chad
Richard actually brings up a good point, which answers another question
Chad had for me: exactly how many files do I edit? Which directly
impacts the "directory pollution" problem I've been talking about.
There are essentially three scenarios:
(a) FV is turned on on a per-file basis
(b) FV is turned on on a per-directory basis
(c) FV is turned on on a per-filesystem basis
Now, I think we can all see that you get geometic file explosion in case
(c), as absolutely anything that writes to the filesystem gets
versioned. Things like Web Browser caches alone would kill you.
Web browser caches (as normally used) would *never* generate a single
additional file version. The web browsers use a naming algorithm to
prevent overwriting the same file, and that's the situation when a new
version is created. They delete the files they decide they don't need
directly, rather than by overwriting the same name.
Your use of "writes to the filesystem" suggests to me you're thinking
of a different implementation of versioning than was in TOPS-20 and
VMS, and that (I think) most of us are discussing here. The kind of
versioning I'm talking about works by keep old versions of a file
*when it's overwritten by a new version*. It's the operation of
creating a new file with the same name as an old file that triggers
it; in current Unix semantics the old file is deleted, but in the kind
of FV I'm talking about, the old version is *kept* and the new version
is given an incremented version number to keep the names unique.
It has nothing to do with writing to files; if you update a file in
place, a new version isn't generated.
--
David Dyer-Bennet, <mailto:[EMAIL PROTECTED]>, <http://www.dd-b.net/dd-b/>
RKBA: <http://www.dd-b.net/carry/>
Pics: <http://www.dd-b.net/dd-b/SnapshotAlbum/>
Dragaera/Steven Brust: <http://dragaera.info/>
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