[sldev] [ARCH] Certified HTTP Project Update - Oct 25

[Ryan Williams (Which)]

Argent Stonecutter wrote:
> I thought object updates could be partial, and if the object isn't
> physical they won't be repeated... how often do "routine" object
> updates happen then?
>
> Now that you mention it, object updates would be a good application
> for something like this. You'd send a nonce with each update, and with
> each partial update the nonce for the last update of the object, and
> if it doesn't match you request a full update. Send a sequence number
> with the update and you can tell if you missed one, and periodically
> send back a "mass ack" with a list of missed sequence numbers since
> the last mass ack, with some kind of RLL coding for big gaps. The sim
> would only need to keep track of a small number of sequence numbers
> for each object for each client... if they overflow it can just switch
> to full updates for the object until it gets an ack that'll let it
> clear them.
>
> Or do you already do something like that?
>
Actually, I have a really poor knowledge of how it currently works.  So,
uh, maybe!

The way it works now (whatever that is) is decent.  It could definitely
be improved, but it's remarkable how well it's held up over time, as
other parts of Second Life have shown their age more quickly.

> Partly true. Control chat doesn't need to be in order, and does need
> to be timely. I don't know how to distinguish that, though, and having
> some kind of "user control" mechanism for the future would be a better
> fix than some kind of "negative channels are UDP" hack.
Hell yeah.  Using chat for controlling vehicles is a huge hack, though I
love that it works.

-RYaN