Interesting presentation about the underlying design of SL

Bartholomew Gallacher 26. März 2007 0 Kommentare

Back in 2006 there’s been an interesting presentation about the underlying design principles of Second Life. It’s being hosted at the company website of MySQL.

The presentation goes about 45 pages. The most interesting page is for sure 25, because it gives a big overall picture about the underlying architecture of SL.

So, here without further fanfare, is this picture:

As you can see, there are quite many parts behind Second Life that we are normally not really aware of. The only part we can already build ourselfs is the viewer. This is now available as the real deal under the GPLv2 already.

But the rest – well… the most important part is the simulator. That’s the machine that’s computing the avatar movement and so on.

When it reboots it’s got to take it’s data from the central database. Once this is done, it should be more or less in an operational state. States and assets of the sim are being saved on an extra machine, the assets server. That’s just a big, clustered filesystem, so there’s not much intelligence on this machine at all. I guess it’s being used to save data in it which needs to become fast available, and of course there’s nothing faster then getting data of a filesystem instead of a database. A database adds for the same task many new layers the request must go through, so that’s quite a good way to speedup things for trivial tasks.

Well, the rest though is in databases, running under MySQL. The "Central" DB, the logging db and a database farm (for things like inventory and so on, I guess). But the simulator does not talk directly with those three databases normally; it talks to them through the dataserver. So, what’s the job of the dataserver? It is to cache requests and take load away from the databases and to deliver the content to the sim.

So, when we download textures, shapes and such, the sim first talks to the dataserver and if it is already cached, the server directly replies instead of asking the database.

The dataserver, though, is one of the bottlenecks of this architecture. Second Life uses at the moment a kind of homebrew protocol for the communication between the dataserver and the sim – this means also between the sim and the viewer. The result is, while it has done its job pretty well in earlier times, it does not scale really well, as it seems.

Scaling could be done, perhaps, but why take the effort in creating an own scaling solution, when you can change the protocol from homebrew-inhouse into a wellknown standard like HTTP, where good, proven and reliable scaling solutions exist already for a long time? So that’s the main reason why LL wants to get rid of this old, homemade protocol, and replace it with HTTP. The sim should be able to talk with the dataserver (in the presentation it’s replaced with a webserver) via HTTP, because it scales much better and more easily.

Ah, yes, and Wilkes gave us also one motto of LL in the presentation: databases are not special. So why optimize them, when you can scale more easily? Well, we’re going to see the impact of the new messaging system real soon since LL is putting a testgrid for it up right now. I hope it’s one step into the right direction to make SL a better experience for all of us.

Oh please, as if the SLLA is not worse enough…

Bartholomew Gallacher 26. März 2007 0 Kommentare

Groan. There is now a new group on the block, calling themselfs the "Second Life Anarchists." Their goals are somewhat similar to the SLLA.

Their main message to us all is something like that:

While we laud LL for their foresight, and technical achievement in bringing SL to be, and find it hard to fault their stewardship of this world to date, we would argue that their management and interference in the goings on here are no longer appropriate nor required.

Neat, hu? But well, what do they really want? It boils down to this point, it seems:

LL has declared land to be in restricted supply. We at SLanarchy despise this and can’t help but think that whatever they were taking when they made this decision was indeed some bad, bad shit indeed. As discussed a few sentences earlier, we see no need for this artificial lack of ’supply‘. SLanarchy would like to propose that SLitizens are smart enough to create and manage their own worlds now, and call for LL to set free the tools required to embark on this unprecedented opportunity to enable every man, woman and child on the planet, to create their own parcel on this, the next digital frontier. Open the source code for the servers LL. Let us, the Slitizens, take on the burden of responsibility for our own future and the creation there of.

So I wonder when this group is demanding Microsoft to opensource Windows under the GPL with the same reasoning…

Or in other words: dream on! Lindenlabs is a company. They need to make money, even more they need to make profit. They’ve got venture capital pumped into them. So their investors want some kind of return of it. How does LL make big bucks at the moment? With land sales.

So while land prices are still up, expect them so trying selling much land, not giving their most valued treasure – the server part – away for free. At least not until they’ve got a new business model, that works equally good.

Opening up the client was a nice move, it made very gentle press on them; but: the client without an open server is not of much value. It’s basically just an empty shell, then. This is like you could get Firefox always for free, but a web server (like Apache) would be only available from one company and you would have to pay for it. That’s the situation with SL at the moment.

How it is going to develop we’re going to see – just remember, we are all here voluntarily, no one presses us into this world, so we all choose to be dependent on LL in this or other kind of ways. Not that I complain.

Blog has moved

Bartholomew Gallacher 25. März 2007 0 Kommentare

This little blog has moved over here! Changes include a different blog engine (Serendipity) which is more easily extendable than WordPress, a new layout and other stuff, too. Well, I guess it was about time, so that I can now continue my sophisticated blogging in even more interesting kind of ways. Or something like that. 

New townhall meeting soon?

Bartholomew Gallacher 24. März 2007 0 Kommentare

It’s been a while since the last town hall meeting has been held, it was back in January about opening the source code of the client and such.

Since the new addition of voice that is going to come to us all on the main grid very soon now is another milestone in the evolution of SL that is going to affect everybody I wonder if and when there is going to eb a townhall meeting about that kind of topic.

„The 13 most beautiful avatars“

Bartholomew Gallacher 23. März 2007 0 Kommentare

There’s an art exhibition right now in New York City with relevance to Second Life. They’re featuring the "13 most beautiful avatars" there on big, big prints.

They’re featuring only portrait shots of them, digitally printed out on 36×48 inch canvas (that’s 91,4 x 121,9 cm, folks). So the things are quite big, you could buy it and hang it over your fireplace, bed, whatever.

Frankly, I don’t know how they were chosen, it seems the taste of the photographers was the judge on it. Some of the avatars, like Aimee Weber, are really well known and I think it’s at least for her more about branding herself and her name than anything else. I also know more beautiful avatars than those on the exhibition, but that’s just my taste, of course and YMMV, like always.

Frankly said, I would not buy such a portrait and hang it anywhere; instead I would try to spot them and make a photo of them myself (haha, just kidding). Well, I spotted Aimee Weber a while ago in the Avastar building, in which she was evolved – whatever.

No, but really I would buy – if so – or print something from the IRTC instead. For example, something like this picture here. They all have a more aesthetic value than anything that can be taken on SL at all, since it’s about raytracing there.

„What’s so outstanding about SL that so many people are criticizing it?“

Bartholomew Gallacher 23. März 2007 0 Kommentare

Pham Neutra is asking in one of his blog post what’s so outstanding about Second Life that so many people are criticizing it right now. He only knows one another thing where the discussion about it is equally emotionally heated – nuclear plants.

Well, so why are so many people criticizing it? Because it’s new, it’s hip to criticize it, they don’t have a clue. Just take a look at earlier things like Rock’n’Roll, Skateboards, whatever – when they first became mainstream, many criticized them, there’s a thick, red line of such debates in history. Period.

SL Herald, Plastic Duck and so on

Bartholomew Gallacher 23. März 2007 0 Kommentare

The Second Life Herald is running an article about Plastic Duck’s job inquiry at LL and how the CEO responded. Well, beside the obvious commentary from Prokofy Neva (gna… if he’s so horrible, just shut up and sue him!) it’s a rather heated debate.

Well, from the point of view of Lindenlabs Plastic Duck must be somewhat hard to come by. He’s caused much trouble all over, but also seems to be a very good programmer who knows, what he’s doing. But would it be wise to hire him from LLs point of view, if he really wanted to join LL? I guess not. Therefore it seems he’s done too much in the past to be accepted by the community. Period.

Finding out every stream URL you always wanted to know

Bartholomew Gallacher 20. März 2007 2 Kommentare

Gentle reader, you always wanted to know from which URL the music is streaming into a hip location, but the owner of it is sitting on this like a secret and using network sniffers like Wireshark is beyond your capabilities? Fear no more! I’ve got the solution right for you, it’s plain and simple in your standard client, just a view fingertips away!

So, this is inspired by a post of Torley Linden about the still outstanding teleporting issues and what to do against them, since this is know to be buggy since quite a time.

So, the first step you should do is simple – just press Ctrl+Alt+V. This gives you access to menu entries in the client, which are normally available to Linden Lab employees only. It’s safe, since those are not going to work for you anyway, but this step is crucial.

The second step is simple: just go to the location, of which you want to know the stream URL, open the „About Land“ dialogue and go to the media tab. The stream URL is now going to be displayed to you no matter if you are the land owner or not. That’s it, it’s so simple.

And as a demonstration how this might look is here an in game snapshow of the stream URL of Phat Cat’s; the most vital part is grayed out by myself in this screenshot, since I don’t want to spoil the URL here. But trust me, it works, give it a try, if you’re interested in.

Another critical article about SL

Bartholomew Gallacher 18. März 2007 0 Kommentare

Mario Sixtus, a well known German freelancing journalist, wrote a very critical article about Second Life and the hype around it in his blog. Translated it’s called somewhat like „My ultimately last words about Second Life“.

His message is basically this: modern web platforms have reached today an abstract level, that constantly refuses to be compared with RL equivalencies. Journalists actually have to learn something new if they want to write about those services.

On the other side there’s Second Life: nice, colorful pictures, you can actually show nice movies of the world in your articles, no need anymore to show boring sequences with someone just hacking onto his keyboard, and, oh, look, how convenient, it’s all about sex, so let’s write about it! Ah, a millionaire already? Let’s write about it!

It’s also no wonder, according to Sixtus, that the industry is hailing SL as it’s saviour, since old strategies did not work very well in the WWW and you actually have to learn something new.

In Second Life it’s just like in the good old times[tm]: making ads, opening branches, having nice launches and so on and on… and even better, this time you’ve got the press on YOUR side! Amazing!

Sixtus‘ conclusion is: Second Life is not the internet, it’s a biotop, a bubble for people who fear the future.  So it’s target group is for people who still think in terms of the old century; it’s basically the past, but not the future.

It’s nice to have dreams…

Bartholomew Gallacher 17. März 2007 0 Kommentare

…like the CTO of Lindenlabs who dreams of an infrastructure that can support 10 millions of concurrent logins or like the CEO of Lindenlabs who dreams of 1.5 billion people online in Second Life or virtual worlds (the statement is in the current Avastar) but at the moment I and most other people would be very glad already when SL would scale better when more than 30.000 people are online at the same time.

This seems to be the magic number at the moment after which SL goes haywire.