Talk:Project Motivation

Scaling for events

I would like to add more scary numbers to the main namespace here.

• If N people are interested in an event today, and the population grows tomorrow by a factor of M, then tomorrow N*M people will be interested in that event, assuming unchanging population demographics.

• Every live music event by the top few SL musicians maxes out their event sim: let's assume that this means 100 people, although the demand is undoubtedly higher already but not satisfied. SL currently has just under 10m registered residents. If the scary number for total population size is 2 billion, then the scary number for event interest is 100*2000/10 = 20,000 to an event region, given unchanging demographics.

• Of course, worldwide we do not have an unchanging demographic, but no matter by how much you want to reduce this figure as a result of this, the answer is still collosal. And bear in mind that there is much uniformity in eastern populations, just as there is in the west, so event interest within each cultural domain will be huge. And of course many events are cross-cultural.

• Which brings me to the issue that nobody seems to want to tackle: the new architecture needs scalability for events.

• While I recognize fully that there are monumental hurdles in the way of achieving this, it is just an engineering problem with a number of known partial solutions and amenable to tradeoffs. Worse, not addressing it will leave us exactly where we are today, with zero scalability for events. And, very unhappily, SL will become the virtual world where almost everybody is barred from their favorite event. 19,900 people out of every 20,000 will have to stay at home. That's not the future system we want to build, in my view.

• Please add at least 10,000 per region to the scary numbers, to focus the mind. --Morgaine Dinova 21:07, 24 September 2007 (PDT)

• I mentioned this at Zero's Office Hours today, but no traffic yet, so added it myself. --Morgaine Dinova 17:42, 25 September 2007 (PDT)

Zha's comments on events

The event discussion came up at the AWG kickoff, and comes up from time to time in Zero's office hours. At the heart of the event discussion is the desire to host very large events inside the SecondLife environment. This raises the question, what will 200, 500, 1000, 10,000, 20,000 users be able to do in a single contiguous portion of second life space. Assuming for a moment, we could manage the simulator side space, what would a client see? At 100 avatars in a sim, my current screen is pretty much solid avatars with a cloud of tags floating over them, all in constant motion. (Granted we're also all in concrete, in the current sims, but we'll assume that can be fixed.)

Somewhere north of 500 avatars, I can't see how I could render more than a fraction of them, nor could I interact with more than those I could see right near me. So, and I am quite serious about this question, what are we attempting to achieve. If the answer is "let us all share the stream" I'll point out that the streams are orthogonal to SecondLife. If it is interactivity, in the current style of SecondLife, I'd like to see a use case for how we could produce an interesting user experience with the number of avatars I listed above in ear shot. How fast will the chat window scroll? How fast will people's "nearby" windows update? How many avatars do we expect our scripted objects to be able to sense, and how will we even see most of the avatars

Beyond the user experience, we also should look at some hard technical questions. How many Kbits per seconds of updates are needed to support each of these size points? Can we get that from current networking hardware. Look at these questoins, Simulator to Client, Simulator to adjacent Simulators, and Simulator to utilities, and agent domains.

This isn't a simple "let's quash the idea" post, far from it. But If we are asserting this as a desire, lets actually produce some use cases which describe what we are trying to enable. "20,000 in an event" isn't a requirement I can design against. Give use some use cases which describe the actual user experiences that we wish to enable. Look hard at questions like "How will chat look, how will visibility work, how would scripting behave." Capture these in use cases.

I will suggest, for example, that some use case can be solved by better inter-region behavior. Others, would only be solved by attempting to limit the interactions between avatars in significant ways. Serious discussion, backed by used cases, would be invaluable here.

- User:Zha Ewry 9/25/2007