adding more prim capacity to land!

Gabrielle, you have to take into consideration how computers work. You can't have some prims that are "controlled by a different server", it doesn't work that way. (That's like saying you could drive twice as fast by getting a second car.) I don't think people are being "closed minded". Instead they are taking into account how SL works, and what is feasible.

Try convincing the supermarket that you want to pay for soup independently from soup cans. You want two cansworth of soup, but you only want one can, because its reasonable to expect that someone else wants two cans, but only one cansworth of soup. News item: When you buy soup, you don't get to decide how much goes in a can.

In SL, a sim is a container, and the manifistation of the container is "land". The land is the container, that's how it works.

LL *does* have plans in the long run to increase the number of prims you are allowed. It requires technology and programming improvements that take time to unfold.

Also, LL must balance their costs against what people are willing to pay. Maybe they could run one sim per server instead of two, and if they did that, they could allow more prims per sim. Who's going to pay the half-million US$ that would cost for the new servers, plus the overhead of running twice as many servers? Do you think its reasonable to double all the account and tier prices across the board, so everyone should pay twice as much and get twice as many prims? If you want twice as many prims, you can pay twice as much now without making ME pay twice as much too.

Schemes to allocate prims other ways have been tried, the current way is the best way on balance. It has advantages and disadvantages. It is very simple, fair, and has no administrative overhead.

The flip side of "you get what you pay for" is that you have to pay for what you get. I think people drastically underestimate how much it would cost to make suggested changes. LL must balance the overall cost to the consumer with their costs to for the programming, administration, hardware and maintenance. Those costs are HUGE. Making a change has a HUGE cost. There is a lot of demand for a lot of changes; they must balance all the competing interests. I think the current land tier system does that best.

Buster

Those without bona fides should abstain from suggesting sweeping changes to the system unless they possess the technical credibility required to argue for such a thing.

Oh, boy... There are a number of missconceptions running rampant in this thread, chasing their own tails and getting us nowhere. Can I start with some first principles here, and then see where that takes us? (Skip to my next message for a summary, but read what I have here if you have issues with my comments.)


The top 4 reasons there is a "prim limit"...


1) What can the CLIENT computers handle?

This is the BIG one. Linden Lab has no control over the client computer hardware, AND they want Second Life to run on as wide a range of computers as possible, from old college hand-me-downs to top-o-da-line leet gaming rigs. And they want it to look and perform the same across them all. So, how much 3D data can the average target computer display at one time? With other single-player and oneline games, the client has a copy of the whole game world, optimized and streamlined. (Only one side of the room's walls exist, since you never see the other side, for example.) But in Second Life, the world is in constant flux so that style of optimization isn't done. (Though it MIGHT be in the future!)

If one person owned all the prims in a sim (ignoring how much land they own, for the moment) and put them all in one spot - all 15,000 - just you try to look at that pile without your FPS grinding to a crawl. CLIENT frames per second, that is... The server could care less where in the sim the prims are displayed. For purely visual purposes, position is just a vector (<128,128,30> to the server, another bit of data to transmit. It's the CLIENT that puts them together.

And when too many are on screen and in range at one time, the client computer's fps will go down.

SOLUTION: Force the prims to be more spread out by tying them to subdivided locations within the sim. As long as there are many owners in a sim, the prims will be automatically spread out, and this "bunching" problem will be avoided.

CURRENT FLAW: You CAN buy a whole sim, mainland or island, and put ALL 15,000 prims in one spot. (But no one will want to party there, let me tell you!)



2) Physics

This one IS on the server side. No physics are handled on the client end, not even collision. Which is why you can bump into a building that hasn't rezed yet... You send how you want to move to the server, it has all the prims in a physical model and can tell if you are blocked or can move freely, and sends your new posisition reflecting this back to the client code to update where you seem to be in your view.

When you alt-drag your "camera" around the world independent of where your avatar is, you aren't doing this server communication. That is why it's so much faster, smoother, and more responsive than walking or flying. It's all client-side.

But physics isn't just bumping into things... Objects can be physical too. At the moment, there is no limit on how many of the 15,000 prims can be physical. All of them COULD be! But again, you won't catch ME going to such a sim. Instead of the client frame rates being slow, the server will be grinding. Not only that, but any clients in or near that server will be getting 15,000 position/rotation updates. That sort of thing is beyond the capabilities of server, network, AND client.

SOLUTION: Well, this problem really doesn't have a current solution. Sims slow down under heavy physics drains and people there complain. There's nothing to counter this problem automatically.


3) Space is an illusion...

What is space in a computer simulation? Coordinates. Numbers. This thing is HERE, that thing is THERE... The empty space between them is defined by their relative positions. How high can you fly in Second Life? Pretty much as high as you want to, no one has ever hit the "glass ceiling" and never will. But, those that have tried have found themselves looking rather mangled as they reverse-plummeted into the sky. Why? Floating point numbers.

An integer has a maximum and minimum value. Your typical 32-bit (32 ones and zeros) integer can hold whole numebrs (no decimal point) from 0 up to 4294967296 or, if you want to have negative numbers too: -2,147,483,648 to 2,147,483,647. That's over 4 billion numbers, and that's a lot of positions. And that's just one dimension, in SL we have three: X, Y, and Z. That gives us almost 10 billion positions!!! "Space is big", right?.

But those positions can't be "meters"... We need centimeters and millimeters. There needs to be a smallest increment so we can position small objects like 1/4 carot diamond earrings. So we cut our scale down so we have a thousand increments inside the space of a meter, for millimeter acuracy. That gives us 10 million positions to play with, which would be a sim 215 meters to a side. Well, our sims are 256 meters to a side and objects can be seen over the borders from other sims, so this just isn't enough room, really. Not only that, but we can go far more than 256 meters into the air.

But that's just with 32-bit integers. Why not 64-bits, or 128-bits. With 128-bits we get how many postions of 3D space? Type this into Google: (2^12^3 and you'll see the number. But using 128-bit integers would require 4 times as much data to be sent, just for a position, and make the LSL scripting language need to use 128 bit numbers too. Computers are only now starting to use 64-bit numbers natively, and most computers are still 32-bit. So for the moment, we're stuck with 32-bits.

Enter the floating point number. These can get VERY big, but you lose accuracy as you go. Since every corner of every prim needs to be on the grid defined with these numbers, the less accurate the numbers are the more mangled an obejct will look because it can't quite put the corners where they should go. With floating point numbers you can be more than accurate enough as long as you aren't too far from zero.

If that was hard to follow, then try imagining these three ways of making a LIFE SIZE image of your hand. First, use one of those desk toys with all the pins in a frame. You can get a pretty detailed likness of your hand. That's what it's like near zero coordinates. Now try to make an image of your hand with a Lite-Brite toy. Not quite as accurate. Now one more time using typical childrens blocks, just lay them out under your hand. Not very accurate at all... That's what it's like at 1,000 meters up.

So floating points give us all the room we need to cover a sim with overlap and all the air space we want, if we can put up with increasing distortions. And on top of that, we can start a new zero point in each sim so that, on the land at least, you never get too far from zero.

So long story short, space is cheap. You can have as much as you want of it, within some limits. "Void" sims run 4 to a server. You could have 100's of sims on a single server if you really wanted to, but you couldn't put any more avatars in it than you could in a single sim. The physics requirement is a constant. And putting lots of people in the same place is what MMO games/environments are all about

FACT: We AREN'T paying for land. Land costs nothing. It's an illusion of numbers.


4) Bandwidth and getting from there to here and back again...

There are limitations to how much data can be sent and how fast it can be sent, both from the server to the client, and from the client to the server. Most of the data starts on the server side and comes down to us clients.

I had a big section in here too, but cut it out because this isn't much of a problem. While you COULD slap 135,000 textures in one sim (do the math) no one is going to. It would be surprising to see a 512 meter plot with 53 textures in use, let alone the max possible of 1053.

People tend to keep texture use down because they want their builds to load as quickly as possible, and because of the need to use the same texture in multiple places, AND because there is a small cost to adding new textures to the server.


And now, for those of you that DID read all of this, let join the ones that skiped it for its length and read the summary post below...

Summary from above:

1) The wide range of capability in the varied client hardware puts the biggest limit on the number of prims that are displayed on a client’s screen at one time. We force the prims to be more spread out by tying them to subdivided locations within the sim. As long as there are many owners in a sim, the prims will be automatically spread out, and this "bunching" problem will be avoided.

2) The more prims there are, the greater the number of potential physical collisions there are, and the harder the server has to work to process them. Again, by spreading out the prims, complex collision situations are avoided.

3) Space is an illusion stemming from numbers. Sims COULD be any size, but as this is an MMO with the purpose of bringing people together, and moving people about has a physical simulation cost, a balance must be struck between space and processing. Too large and the sim will feel under-crowded when technically full, too small and extra cost is needed to add additional server hardware to give players the psychological room they need.

4) By spreading prims out, you reduce the number of textures visible at any one time and that reduces the bandwidth requirements. While this seems unimportant for a single player, when you have an entire sim’s compliment of avatars in a single room, all the textures in that area have to stream to all of their clients, multiplying the bandwidth cost.


So there ARE reasons why prims are limited “resource” to the residents of Second Life.

It becomes only a question of how they should be allotted. Early experiments in alternate distribution schemes showed that paying on a per-prim basis meant that those with a larger reserve of money (L$ or otherwise) up front could pay for a large reserve of primage, and that they were disinclined to “sell” what they weren’t using in case of future need and possible shortage at that time.

The suggestion of allowing land owners to sell their prim rights to other land owners in the same sim would be under the same dark shroud of… Not greed, but investment savvy. Sim residents would buy up offered prim rights so they have them on hand for future projects. Soon, none would be for sale unless someone left that sim.

Then there would be the issue of selling plots that have more or less prim allocation than normal due to previous sale or purchase. Are the sold prims yanked away from the buyees to be returned to the plot for sale? Does the plot have to be sold with non-standard prim limits? Would the plot be unable to sell until its prim limits have been bought and sold back to their original values? Or would prims and land have to be permanently disassociated and newcomers to the sim have to buy them separately?

None of those questions go in very good directions. All of them add complexity, hardship, and strife in exchange for what? The ability to have less land than the prims come with? More land than prims? If there is a set number of prims in a sim and that number can not change (as stated in 1-4 above) then what is wrong with using land as the “box” than the prims come in? What advantage would a la carte prims have that would make it worthwhile to make life more complicated by introducing all these problems and questions?


So there ARE reasons why prims are limited “resource” to the residents of Second Life, and while the paradigm is that we are buying LAND (because that is familiar to us), in reality it is the PRIM allocation we are buying, and the illusionary land that comes with it acts as a easy visual meter as to their quantity.


If you want more prims, BUY them and the box they come in, LAND.

(And if you want a bigger yard, make your avatar and your house smaller… It’s all just a matter of scale, after all.)

you're so closed-minded Tiger.

As a tech worker who has dealt in networking and computers for twenty years, I have to say those word make me cring like I'm about to be whipped.

I got to hear phrases like that everytime the boss decided to throw out the currently working system for the newest fad.

Study the current system first, ask LindenLabs questions, and then we can debate it's function and form. Otherwise, you will not understand the points we are trying to make.

And no, that was not a jibe at you. I've debated on lots of things I knew nothing about.

I also got my hat handed to me nearly every time.

Knowledge is power. Empower thyself and win your war.

^^^^ that was a joke

Whew... I was hoping so.

I try to be so open minded that my brain is in danger of falling out, because only then do I feel I can see all the facts that relate to the issue at hand.

But if I DID want to be close-minded, then the biggest argument for keeping things as they are as that it works.

But that's not enough reason for ME... As the length of my posts above should attest.

Tiger, I almost wish I hadn't made the joke because it compelled you to defend yourself....

YOU are the very last person I would ever question regarding the openess of your mind...some words to describe you would be:

Creative, Talented, Generous, Thoughtful, Considerate, Helpful....

If you thought there was any merit in this idea, I would retract all the strong opposition I typed but never submitted to this thread (I should have about 5 or 6 more posts in this thread, but I decided not to be an jerk).

Thanks,
Champie

Of course it would not double the servers needed!

Infact, it would allow them to get away with LESS servers!

Right now let's say 50 people are paying for 1024m2
plots of land each.... all on the sam server, giving each
of them 234 prim each. If each one of them is not using
their full 234 prims, then some cpu power is not being
used which could be used in some other way, so it's
wasted.

-- and the problem is that a single server only has
so much power it give (15,000 prims worth)

Once that limit is met... you're out of luck.
And that sim can never let people do MORE than
they are doing. Bad.

People willing to pay more for a lag-free experience
can't! -- even if they wanted to.. because lag is tied
to the land/owner of some club/event they have no
control over!

If cpu power could be applied to an avatar... where
a server (or part of one) is not tied to some land, but
rented cpu power paid for by Joe Avatar, which manages
any of his prims set on any land, and handles the rez/display
for his avatar, that puts HIM in direct control of his online
SL experience.

Some who's cheap minded (free account) should expect
less LL resources and more lag. Someone who pays more
should expect more LL resources and no lag, more prims, etc.
It should not matter what sim/land they own.


It seems a server can be divided in to about 128 plots allowing
117 prims each, but I'm SURE it's not a 512m2 plot of bare
land itself that requires 1/128 CPU power from a server. That
amount is taking in to account the over head of having all
117 prims rezzed and probably some extra overhead for AV
attachments, etc.

So, let's say the "land server" when JUST being responsible for
the land could manage 10 times the amount of bare land, or
1,280 plots ! Now, you've just replaced (kinda) 10 servers
that use to manage the land AND the prims, with just 1 server
managing just the land and a little overhead.

However, those 9 "extra" servers would now be used to manage
the prims, attachments, AV display, etc of several residents.
A resident paying $200/mo would get an entire server of their
own which would manage their prims, diplay, etc. All the $5/mo
accounts would get 1/128 part of another server (shared) to
rez and manage their 117 prims.

The difference is that they could have/rent whatever CPU power
they needed, but it does not need to be tied to land ownership,
OR worse yet... a specific single sim!

Gabrielle

ACK !
Why are some people SO dense??

You are STILL associating cpu resources of your neighbors to the LAND!

Stop it!

The idea is to GET AWAY from that!

What you build and your lag is controlled by the amount of CPU
power you rent from LL.... whether an entire CPU all to yourself
for $200/mo (as an entire island is now).... or just 1/128 of a CPU
for $10/mo (as a 512m2 plot of land is now).

What your neighbor builds has NOTHING to do with your lag!
THEIR lag is affected by their builds and how much CPU power
they are renting. YOUR lag has everything to do with ONLY the
CPU power you are renting.

This is DETACHED from the land itself.

Gabrielle

Yeah...

You either don't read, or are incapable of understanding. The limitation of your magical "put it on another server" is that the necessary communication between servers becomes infeasible very quickly. Therefore, neighboring things that interact very often need to be on the same physical server. Therefore, they affect each other no matter how much you wave your hands.

Sorry, I'm going to excuse myself from this discussion from here on in to let the discussion stay polite.

I'm walking away now......

but before I do...Gabrielle, are you sure you want to complain that others are "dense"?

I blame greene for Gabrielle's ignorance

This thread is simply ablaze with bad karma... it makes me greene with envy.

Buster, thanks for your thought out reply..
but you are not using the correct analogy.

A better analogy is series of gears and movable parts put in to motion
by a motor (the cpu). you can only add so many gears and parts
up to the point that your single motor can't support all the piece (lag).
It's like only being able to power a single car off lawn mower motors.
You're going to get a VERY sluggish car!

However, if you divide up the power requirements by having several
motors incharge of different tasks, then you're all good. One motor
(cpu) is responsible for rezzing the raw land (even more land than
it does now because it will ONLY need to handle the raw land). Another
motor can handle 10 residents needs (as they are paying for 1/10
of a CPU for each of them) ... and so on.

I am aware that SL currently does not work that way.
What I'm suggesting is that LL changes it so SL DOES work that way!

Otherwise, you will never be able to have 100 people at a single
event without a ton of lag for everyone... and that is just sad...
when you consider that if this change is made you could have
1,000 people in a single given radius of land without any lag on the
server hosting that radius of land.... because all CPU power for
each of those residents would be managed by different CPU's of
which they are renting.




HUH?
I'm not sure how this applies to what I'm saying.
Even if it DID.. you're mistaken, because at the store I can buy
a small personal sized soup can... a regular sized, or a large
family sized... so yes.. I can get 1 can with whatever amount of
soup fits my needs.




CHANGE THE WAY IT WORKS!
It's a bad design!

You will never be able to get 1000 people in a sim right now
because the lag to everyone would kill you!

If each person was allotted an amount of CPU power from
various servers (just as you think of various sims in use ..
except the CPU is NOT tied to physical land ownership) then
you COULD have 1,000 people on a single plot of land
because different servers would be managing the different
people (again... NOT tied to land)!





I wonder if it's an idea based on the same concept I (along
with others here) are proposing.... vertical scaling envirnment?
.. where cpu power is granted/rented per AV, not land meters.





People who want no lag heavy populated clubs/events could/would
pay for that extra cpu power to allow them to display things properly
and with speed.

Those chat-only type people who don't own land and don't have
premium accounts now can continue to pay nothing, and continue
with their current laggy displays.

I don't own land myself yet... but would STRONGLY consider paying
the small cost (compared to prices of other MMOs) of $5 - $10/mo
for more CPU power which would give me less lag.
I'm sure MANY others would do the same... and there LL would get
there extra income for any additional servers needed.
BUT, as I just said in another post... I think they could actually
get away with LESS than they do now... because current servers
that are doing nothing could be put to work.





HUH?
When did I EVER suggest you pay more?
Right now if you want to rent a certain amount of cpu power (the amount
needed for 117 prims) you pay $10/mo. If you want to control the cpu
power of an entire server you pay $200/mo. Nothing about that pricing
structure would change. Nothing about the prim usage has to change.
The only thing that changes is the fact that your entire server of CPU
power can be applied to your account for rezzing it's 15,000 prims or
crunching numbers for your display, or handling AV attachments no
matter WHERE in the world you are! Not just tied to a plot of land!




No.
This may be the "best" way tried so far, but this is NOT the
best possible way.... which, again... is to have a part of a server
dedicated to your AV as I said above.. which is not tied to land.

I'm not sure what you mean by "no admin overhead". Certainly
the way things are now there IS a limit to how much "stuff" you
can have going on in a plot of land.

It seems VERY simple and fair to me also that you'd be allowed to
pay as much as you are now for "land" as you would for CPU power
and NOT have to have it tied to a plot of land. Those who pay more
now, get more cpu resource... those who pay more with the new
idea get more cpu resource... in fact the SAME amount of cpu resource!
How is that any less simple or fair?





I agree... and more people would be willing to pay for CPU that
gives them less lag ANYWHERE than are now willing to pay for
"land" which gives them cpu resources stuck in a specific sim.
[/QUOTE]


Gabrielle

PS. Buster.... are you a land baron?
Are you worried that detaching CPU power from land would mean that people
no longer need to buy land to control resources, and thus hurting your
land business??

I feel that you might be bias on the side of wanting what's best for your
land company than what's best for the SL community, but as a biz person
myself, I do know where you might be coming from on that.

But what if I'm willing to pay more for more LL server resources to
crunch my AV's numbers faster? Buying more "land" does not do that.

What if I dont need a large plot of land, but do want to use
a lot of prims? Right now I'm limited, but I will accept your
solution of "just buy mor land" .... except that if I'm blocked in
(surround) by other land owners who do not want to sell, then
I'm out of luck!

What if I want a LARGE yard area and small house with very
low prims usage? Now I'm forced to buy a LOT of land and pay
a LARGE tier cost, but I'm using very little CPU resources!
What a waste!


All of the problems above could be solved by detaching CPU
resource renting from the amount of land ownership in a
specific sim.... and instead renting CPU power on a basis of
per resident/AV.

The amount of land I own should not be any basis on how
much CPU power I consume (for which I should be able
to directly rent for LL seperately).

Gabrielle

Your gapingly flawed technical "solution" makes Baby Jesus cry.

WHOA!
Just because I said I was new to SL and not sure exactly how
LL has implemented their programming, does NOT mean I am
new to computer or the way they work!

Just for the record I've been programming since 1979 at the
age of 9yrs old when my father bought a Tandy Model II for
a bookstore he owned. Computers have been my life ever
since, and I've done MANY things since then including building
and selling my own PCs from scratch, teaching myself C and
various other languages as I've had the need/desire, running
my own 26 line social BBS in the mid '90s, doing contracting /
consulting work on Linux servers and networks.

I know very well what computers CAN do !!

And I see a way the SL environment could be made
much more robust with changes like this one.

My comment was not saying I'm dumb about computers,
but rather saying I am not a programmer at LL who's
familiar with how they have their servers programmed
to handle the load.

Are any of you programmers who work for LL and know
more about the REAL technical aspects of how they have
things working? or is everyone here just kinda guessing?

If someone DOES know for SURE... I'd be very interested
in hearing what THEY have to say!






How exactly do I do that? Is their biz model of how the
servers handle the load posted somewhere? How did you
get this "inside" knowledge of how they do work, and on
what basis you are trying to make your points?
--- I'm not trying to jab at you.... if you've acquired some
inside information I'm honestly interested in knowing where
and how you got it so I can read up myself.




Heh... no... I don't think anyone here is jabbing at me
At least not yet! HA !

We're all trying to discuss some ways to handle cpu usage, prims,
land, and the like. I HOPE we are all doing this with the best
interest of the SL community in mind, although for the land barons
I can see how they would put their businesses first, and I can't
say I would blame any one of them that might be doing that.

As far as debating about topics I don't know... and gaining the
power of knowledge... again... my first paragraph. I do know
quite a bit about computers, programming and networks. I would
say my 26 years of programming experience and working with
computers gives me more knowledge than a majority
of the people in SL.

Again... where did you gain your knowledge about LL inner workings?
I AM interested in enpowering myself

Gabrielle

Are you familiar with how clusters work?
many computers working together to solve problems faster by
combining their CPU resources?

I think they do talk very quickly... quick enough for our needs here.

That is easily sig line material. Thanks.

Champie,

I'm sorry to have bruised your ego if you thought I was refering
to you. I don't know if you are one of the posters I had considered
dense or not. I know I did not name names.... but if you wish to
imply that I am dense I won't backlash toward you.

I would say that I am more open minded to alternate ideas,
rather than being close-minded to "this is the way it HAS to be!"

Are you suggesting I'm dense in the fact that I continue
to see an alternative?? GEEeee I'm glad Columbus didn't
stop proving the world was not flat when every else called
him dense for not being able to get it through his head that
"the world is flat.. and that is the way it is".

When I was talking about dense people I was talking about
those people who continue and continue to reply to my posts
with comments that show they are still linking the idea of
prims with land ownership after I've said dozens and dozens
of times that is NOT what I'm suggesting.

If I tell you 50 times that i own a pet, and you continue to
make references suggesting that I do not own a pet, then
you are probably dense... or just trying to pick a fight, which
I don't think is the case with anyone here.

Obviously because we (supporting vertical scaling) are talking
about something that is a totally new idea .. and is causing
people to re-think the way SL is currently set up.. then I can
see how people just might not "get it" right away... need time
for it to sink in , or make sense...

Some people are just a bit more dense than others and it
takes extra time for new concepts to sink in! it's not a
terrible thing... but IS frustrating to the person who seems
to have to repeat themselves 50 times with the same statement

Ardith...

I am very interested in this topic (obviously)...

I feel I do have a good solution, but that it's either hard
for me to explain, or difficult for others to grasp.

I have yet to read someone post a reason it's
technically flawed. Do you have some techincal
reason that would keep a servers CPU from managing
the number crunching on a per AV basis?

Notice you missed the first post on this:

Are you paying for the New Second Life?

Really! You want to basicly throw out the current client/server software and build the data storage and communcation system from scratch.

And if you can pay for it, why not create a competing project and prove how much better your design is. Otherwise, you're trying to teach Stephen King how to write a novel.

Now seriously, I read every post you have made, and am beginning to thing you are playing devils advocate. You just want to argue. The fact you have little concept of the problems with having visable prims causing equally slow fram rates on the client machine proves to me you do not understand the tech involved in this case.

Seriously, explain to me the following:

1. How does your system avoid the problem with a person buying virtually unlimited prims and building something in one sim, thereby crashing anyone within draw distance when they try to view it. This is a limit of the CLIENT's video technology and available bandwidth.

2. How does your system deal with the increase network traffic for prim servers that are not attached to the land, and thereby have to bearing on draw distance? What about prims that are in one 'place' that are fragmented across several servers? Does each prim not hold data on it's server of origin? How much cross-talk will be needed to maintain this on the LL networks?

3. At what point will the crosstalk reach critical mass and overwhealm the network? What do you do when the prims per prim server are fragmented across the entire netowork, meaning that every place must talk to hundreds of server just to rez a house?

Answer those for me, in technical detail, and we can then also solve a lot of the problems suffered by Artificial Intelligence systems tested over the last few years.

Later,