Programming

Gentle reader,

today I want to talk a little about the realXtend project which came upon my radar recently and impressed me great lengths. Their goal is, put in simple terms, to develop the InterGrid about which Gwyneth Llewellyn spoke recently in one of her own blog posts. Well, she even mentions the project in her post.

The InterGrid, put in simple terms again, is the ability to make your own region/regions/grid and take your avatar on grid A, B or C and also take the inventory of it with you. This means your avatar becomes quite more flexible, it can travel around the different grids if done correctly, but also there's quite much work to do until that goal is going to be achieved. This project is using OpenSim as their platform for serving regions, they've already enhanced it with quite much advanced and sophisticated features and also forked the Second Life viewer into an own thing, although this can still connect to the Second Life grid in a compatibility mode.

The realXtend project is backed up by two Finnish companies and around 20 people working on it, programmers, content creators and graphic designers, so a good size but still small compared to the staff of Linden Lab.

Contrary to the culture of Linden Lab, though, they've got a roadmap, and since they're contributing to OpenSim, parts of it overlap with the roadmap of that project, too. Having a roadmap never hurts, on the contrary, it is always nice to have and a good thing for all participating people.

In a recent interview one of the driving forces behind realXtend, the CEO of one of the companies backing it up named Tony Manninen, gave us a very interesting peace of his mind and his over all vision for the project:

Me: And how will the work you have done on the avatar server alleviate this problem unless SL, WoW and other cooperate on interoperability?

Tony: Think of it more like the 3d web. realXtend/OpenSim is like the Apache of virtual worlds, rexViewer is the Mozilla or Firefox of whatever. When "surfing" the web, you are not constantly required to prove and change your identity when loading different pages.

And this line is quite interesting for all of us. Apache is today the work horse of most web servers on the planet, its market share is around 51% in April 2008. But what many people don't know is how Apache started and how it became the king of the hill. In former times, when Apache was non existant, there's been another 800 pound gorilla of webserving software called NCSA httpd. This was back then the leading webserver under an opensource license. Apache just started as a patchset (Apache was just the nickname for "a patch" first only or more precise "a patchy server") way back then for NCSA httpd, adding features many people wanted but the maintainers of NCSA httpd were unable or unwilling to include. So over the time the patch set became more and more important, popular and turned into an own piece of software, winning big grounds against its father until NCSA httpd became obsolete and went into insignificance.

So, what does that mean when talking about Second Life? Simply: realXtend could be the nail into the coffin of Second Life.

So, what's in realXtend viewer and OpenSim already, that would be nice to have in Second Life, but isn't there (yet)? Among already implemented features those biggies:

• the ability to host your own region somewhere on a server of your choice and to connect it to the grid (many would like that since the tiers you've got to pay for Linden Lab are quite expensive),
• the use of a more advanced opensource renderer named OGRE, which also is going to support DirectX rendering on Windows platforms,
• coming with this renderer real time lights and shadows of objects,
• web on a prim,
• builtin VNC viewer for desktop sharing,
• VOIP client and 3d audio rendernig,
• meshes instead of prims - this means you can build far more advanced structures, also build stuff in normal programs instead of the client and import them, which adds to a good graphics experience quite much, but also means a slightly longer loading time perhaps, but still many would applaud them in SL and with right,
• quite more sophisticated avatar meshes, everything can be an avatar, e.g. also mushrooms (this example is included) or a bad snowman,
• Python scripting,
• teleports between realXtend and Secondlife,
• script controlled teleports,
• centralised avatar storage to move the avatar between different grids,
• multiple streaming URLs per parcel,
• and others,

but those are the real biggies. If you also take into account that it just took realXtend to implement those features around four (!) months of time you'll really have to wonder why Linden Lab hasn't done that themselfes already!

Among the roadmapped features you'll find those things:

• Direct3D rendering on windows platforms,
• support for OGG Vorbis,
• support for video codecs beside Quicktime,
• Weather support,
• inverse kinematics,
• avatar face/head animation based on live video camera data,
• lip sync for VOIP,
• cloth physics,
• vehicle support,
• the ability to hold more than 100 avatars at the same time in one region by splitting up the region on several hosts and letting them do their work,
• and others.

So what we'll have here is a real ambitious project to build the InterGrid with nice goals, but they're not only having a roadmap, seems they've already been able so far to deliver their planned features and are going to be in the future, too, in many parts they're already ahead of Second Life quite much.

To put it short: what we've got here is a major competitor emerging for Second Life and even more so on a very rapid speed! Linden Lab is still ahead of its competition somewhat, but realXtend is gaining ground and its gaining it quickly so that Linden Lab should really be make up its mind now what they're planning with the platform in the future, otherwise it is quite possible that they are going to face the same fate as NCSA httpd or Netscape: the technic will remain, but innovations are coming from other sources and the people behind the initial project are loosing the grip on it.

Technorati : business, development, programming, realxtend, second life
Del.icio.us : business, development, programming, realxtend, second life

Since the opensourcing of the client side of Second Life there have been some more or less interesting projects going on in forking the browser or developing it into something better/more.

Some projects especially are worth mentioning there:

• ShoopedLife. This is basically a viewer that people use who are concerned about their anonimity (haha!). Well, the original client sends some kind of information about your hardware (seems to be the MAC-address of your network interface and the primary partition ID of your first hard disk drive) to the LL server to identify your computer regardless of your login, so that they can permban you if necessary. ShoopedLife circumvents this by sending just some random address instead, so that you can still login even if banned. Griefers love this client very much because it allows them to still login in such a case. Of course, you cannot login with the old account but are then able to make just a new account with trash mail address since Linden Lab will be unable to identify your computer.
• realXtend viewer. The target audience of this project is much broader than ShoopedLife. realXtend is a fork of Second Life, so to speak, it has a Second Life compatibility mode builtin but also can connect to much more in graphic terms advanced OpenSim-grids, which is it real use for now. At the moment it's only available under Windows, Linux and Macintosh are going to follow later. Although still in the beginning, this project already shows much promise and is for sure going to be a real competitor for Second Life.
• RestrainedLife viewer. That's for the BDSM-lovers under the players. It let's the master control certain aspects of the subs viewer, e.g. attachments cannot be taken off anymore, communication can be blocked of the subs and other aspects can be controlled by the master, too. So - not everybody's kind of viewer, but for sure subs are going to love it to be in control of their master, if they bought the right in world tools for it, that is. This viewer is for sure not for the normal audience of Second Life.

Technorati : development, open source, programming, second life, viewers

In business, like almost everywhere else, it's either riding the wave or getting lost when it waves above you. Making a revolution or suffering a revolution.

Lindenlab for long has been riding the wave. Now, that the hype has somewhat gone, it needs to establish Second Life as a more stable platform than it is today, because the competition like OpenSim is catching up and up more and getting stronger. It still has its advantages above other platforms, but needs to communicate those more.

In her latest long essay long running citizen Gwyneth Llewelyn asks about if bad communication practice is the root of all evil, let's just say for short, she's got some valid points. Communication has flown to other kind of meanings, it's still there, but needs to be polished up.

Another main problem she's raising is Lindenlab's missing to produce a roadmap and their inability to work out and work on timelines. That's quite serious stuff.

One of the main problems with SL today is that it doesn't really scale very well. This problem has already been known about the last two years and shows up everyday more and more when a certain avatar threshold of concurrent logins has been met.

The technic behind Second Life has some bottlenecks and shortcomings. Think about it as an analogy like a Ferrari powered by a lawn mower engine. Looks good and all shiny, but cannot deliver the promised power. Yuck.

What Lindenlab has got to do is to build a new engine, that's hard enough, but also to put it in the car while it's running, and that's quite a hard feature to achieve. We'll see if it ever happens or not.

Technorati : programming, second life

Some days ago there's been the news that IBM is going to build their own server farm with the Second Life server side on it.

Well, frankly said, I can understand them. That convoluted mess that Second Life today is is all but a worthwile investment if you're a company. If you want to have a good experience with it, better stay away from the main grid and build your own farm, your own island.

If you're thinking about investing in SL, better do it when the grid has more stabilized. At the moment this would just be a great waste of money in my opinion given the bad performance all inhabitants of Second Life have been experiencing since months now.

Technorati : business, downtime, reliability, second life

Nichlaz Beresford, a resident well known for his own sat of patches for the official browser, quitted some days ago very frustrated providing them.

Many residents mourn about the loss of this talented programmer and his browser, because for many people his browser gave far more better gaming experience, meaning mostly stability and speed, to Second Life than the official does for them. His work has been well appreciated in the community which used his browsers.

The reasons listed by him for quitting making a better browser are mainly:

• he wanted to create his own vision of browser, but has been unable to do so since he was mainly busy ironing out bug after bug after bug,
• the Lindens don't really care for bug fixes coming from third parties any more, most times they just plainly ignore them and
• considering the bad state the browser and platform is in now he would have start all over again.

So, the community loses a quite talented programmer who probably would have been a very good bug hunter and much, much more. That's sad.

By the way, there's still no new CTO at Lindenlab, so it seems. Wonder how they manage to run so long without someone leading the techies.

Technorati : programming, second life

Dazzle looks quite blue, when you use it, but aside that it's still the old Lindenlab viewer, all the same menus and such, nothing new in it. Yet.

That's the difference with the OnRez Viewer. When it became public available, it had some innovations in it like the in-built webbrowser, the renovated search and others. OnRez itself was innovative, Dazzle on its own is just a new skin for the client, nothing more.

But what the client really needs is a rearrangement and rethinking of some menus, interfaces and much more, which hasn't happened in Dazzle - yet. So in that point Dazzle is simple disappointing at the moment.

There are still many fields in which Second Life gets new development, a good thing, if you ask me. But since those fields are quite diverse, there are now so many first look and beta viewers around, that it get's troublesome to test them all out. Don't believe me? Well, for Windows, there are those viewers beside the official one around:

• the release candidate viewer (version 1.19.0.2),
• the Windlight first look viewer,
• the Dazzle first look viewer and finally
• the beta test grid viewer.

A big matter of choice and on the impact on the whole data system is of course the operating system - Lindenlab runs Linux - and of the underlying file system. According to the SL history wiki all the database servers of Lindenlabs use ext3 as default filesystem, after they uses ReiserFS 3 for a while and evaluated XFS. Ext3 is really a bad choice if you need the best performance your hardware can give.

Well, why that? There are some reasons. There's this interesting IRC log of MySQL employee Kristian Köhntopp. Köhntopp is quite well known for his articles about computer topics and such. This IRC log is about which file system you should choose for a database server in general, but you can take his views of course too on the databases empowering Second Life.

Well, so what's wrong with ext3 as filesystem for a database server according to Mr. Köhntopp and what's ok about it? Several things:

• the amount of files in a directory doesn't really matter anymore with ext3 compared to filesystems like XFS when you've created the ext3-filesystem with the option dir_index.
• A big disadvantage is that ext3 is flushing its log quite irregularly. Meaning: the execution times of certain queries in MySQL can differ quite a lot.
• Another disadvantage is that ext3 does not perform very well if many concurrent clients are connecting read/write, in numbers from 10-50. If only running a single thread, ext3 is mostly expected to be faster than XFS. But when running with many concurrent clients - and that's what we got sure in Second Life - XFS beats ext3 hands down.
• XFS has in contrast to ext3 way much better flush times, they are more regular, and it's much better at preventing the fragmentation of files.
• Ext3 is making "block marmelade", meaning inter chained files, if some files in the same directory are growing at the same time; XFS is good at preventing such a thing.

In conclusion Köhntopp states that ext2 (which is the base of ext3) is depending on the state of art around 1984. XFS on the contrary has been build on papers around 1994, meaning it's younger and having a bigger code base. This means, that XFS might have more errors still than ext3 but on features that ext3 doesn't have.

Oh, and by the way, according to this blog entry from 2005 about the switch back to ext3 from Mark Linden he hasn't really understand what a journaling file system is for. If you take a look at the 2nd mail on this link, you see what Theodore T'so means. But keeping the data intact is not for what the journaling file system has been made. It has been made to keep the filesystem itself intact.

If you want to have an intact database after a crash, use an ACID-compliant one, like the InnoDB-Engine of MySQL.

So what's to say in conclusion? If Lindenlab is still using only ext3 as filesystem for all of their database servers and those servers normally have many concurrent read/write clients around 10-50 or more, they're denying themself from the speed a decent filesystem could give them and really, really should consider moving to another filesystem like XFS. This would be also one good explanation why e.g. the asset server is so damn slow - always, because the filesystem is slow.

This is first going to be a change under the hood; Lindenlab expects a more reliable SL experience out of it. So you should not expect big changes in the beginning.

Later this could lead perhaps to better prims per vehicle, since many ppl awaited this feature for long. We are going to see.

The exploit used has been reported already at 12th February 2006 and still remains unfixed. They are claiming it is hard to fix, but hey, after more than a year and it being abused to attack the grid, it is time now to do something against it! Neva claims, that the purpose of those attacks is to make Second Life unusable for good use like the Relay for Life event last weekend. Hm, some logic in it, could be, for sure if it was attack this event could have been a worthwhile target for griefers.

What are the conclusions? We are never going to know, if those problems were a gridwide attack of griefers or not, until the Lindens are going to tell us. Some things are clearly pointing into that direction. But if it was a griefer attack, the Lindens should tell so and don't leave us in the dark about it.