[Opensim-dev] Proposal to eliminate the name, description and invType fields from the assets db table

[Dahlia Trimble]

Thanks for the great explantion Melanie.

There was recently a discussion in sldev about asset garbage collection in
Linden Lab's servers. Apparently they search for references for all assets
in inventories, scripts, prim inventories, notecards, and probably a few
places I cant think of offhand. If an asset is found to be unreferenced, the
process will delete it. This was discussed as some people were talking about
obfuscating scripts to prevent copying, and a linden was asking them not to
do this as it could fool the asset garbage collector into thinking an asset
was unreferenced if the only reference was in an obfuscated script.

The discussion was around May 19th and can be found in the sldev mailing
list archives.

On Mon, Jun 23, 2008 at 2:51 AM, Melanie <melanie at t-data.com> wrote:

> Yes. Assets are never given. The are always shared. You pass around
> references, and permissions, names, descriptions, etc, apply to
> those references only.
> The viewer employs a transaction system to keep you from creating
> references to arbitrary assets. If you could, you'd have a copy.
>
> Assets are immutable and implicitly shared. Any copy of an item
> shares the asset with it's original.
>
> Texture, animation and sound are immutable items. There are no
> changeable parts to the asset. All others get copied only when
> changed (copy-on-write).
>
> So, at any given time, any asset can be referenced by any number of
> people.
> That is also the reason why no asset table cleanup is possible. You
> just don't know if something is referenced. It's not just user
> inventories, but also prim inventories and textures on prims, as
> well as references to textures and sounds by UUID in scripts.
>
> So, asset naming is really a nonsense operation.
>
> Melanie
>
>
> Mike Mazur wrote:
> > Hi,
> >
> > On Mon, 23 Jun 2008 09:17:20 +0100
> > Melanie <melanie at t-data.com> wrote:
> >
> >> no. Assets are shared. If I give you an item, both items will refer
> >> to the same asset. Who will have the right to rename?
> >
> > OK, let's see if I can understand this.
> >
> > If you give me an item, how many items are there? I assume if you give
> > me an item it's removed from your inventory and placed into mine. There
> > is only one reference to the asset.
> >
> > If you copy the item and give me a copy, what happens? The reference is
> > copied, while the asset is not? In that case we have two references,
> > both referring to the same asset as you say.
> >
> > I guess if you copy an item and give me the copy, a new copy of the
> > asset is _not_ made because that would clutter up the DB with possibly
> > thousands of identical assets?
> >
> > Thanks!
> > Mike
> > _______________________________________________
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> >
> >
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