Deano of Ninja Theory talks about PS3 Memory Management (Blog)

[BlueTsunami]

You would think that as we get more and more memory in consoles, that memory management would get easier but alas its not to be…

PS3 has 512Mb of RAM in total, which is a sizeable chunk when compared with the last generation of consoles (64Mb in the Xbox). The problem is that, we want to do much more and we want to do it ‘easier‘.

So where does it all go…

Well first you have to OS thats going to take a bit of the apple. And its a sizeable chunk…

Then we need space for all these lovely HDR AA framebuffers and render targets.

Then we have textures and geometry and least we forget animation data and sound. These content items consume the vast majority of the RAM. Off the top of my head its in the region of about 300Mb in total! This is all streamed as well, so be glad you have a nice big disk to put things on…

So whats left? This gets to be used by code and the actual run-time heap. And suddenly all those ‘high level’ C++ things don’t seem like such a good idea. XML, std::strings, std::maps etc. consume memory like its going out of fashion… then something wants some more for pushbuffers and havok wants some for collision meshes and then there are load buffers and etc.

The grand result is you find your way over memory budget and whats potentially worse, its a really hard problem to track. We are a big team that can produce far more resources than I (as Lead Programmer) can cope with… So I have to resort to forgetting all this new fancy PC techniques and falling back to the good ol’ fashioned console style system.

Link to the Blog: http://rattie.demon.co.uk/?p=43

1) He talks about a "large disk". It could mean a HDD or a Blu Ray disk (I personally think hes talking about a Blu Ray disk)

2) Streaming off the disk seems to alliviate this problem

3) He also talks about the OS taking a nice chunk of the system memory...I wonder what OS hes talking about...

I like the end of the blog which talks about how PPU and SPU utilization will probably be used years down the line. Its also very interesting that it seems that hes already relying on the disk capacity of the Blu Ray (if hes talking about Blu Ray). I wonder if other development studios are doing the same.

[Crossbar]

Link to the Blog: http://rattie.demon.co.uk/?p=431) He talks about a "large disk". It could mean a HDD or a Blu Ray disk (I personally think hes talking about a Blu Ray disk)

You have a confirmation on that one in a reply by Deano:
By nice big disk I meant Blu-ray not hard disk etc. With a single ‘area’ in our terms (something like a room) being 300Mb of in-game memory you need a fair bit of space on the disk to store it all.

[BlueTsunami]

You have a confirmation on that one in a reply by Deano:

Ahh ok. Just read the comment. It seems as though streaming off the BD is going to become extremley important when trying to utilize the system memory.

[Metal Sphere]

Eh!? What dev kit does Ninja Theory have? I was debating with XB over whether this "bridge kit" exists (RSX + CELL, no BD) but this one has all the pieces of the puzzle in it. The AACS fiddling has to get done soon, lest the console be pushed into the closest oblivion.

[BlueTsunami]

Eh!? What dev kit does Ninja Theory have? I was debating with XB over whether this "bridge kit" exists (RSX + CELL, no BD) but this one has all the pieces of the puzzle in it. The AACS fiddling has to get done soon, lest the console be pushed into the closest oblivion.

They must have the final kit (if BD in the devkit = final kit). So this must be some kinda offhand confirmation of what development kit they have :D

[xbdestroya]

Thanks for posting this here Blue.

Anyway I don't think Deano's reference to 'large discs' being good for what they're doing automatically implies their dev kits have Blu-ray; rather that they're just coding and making the game with Blu-ray's eventual capacity in mind. BUT, I mean they could have 'final' dev kits at the moment as well, this certainly aids the case for it.

I want to reflect on something I've been saying and that Deano touched on. The 'MGS4 on 360' discussion has come up a couple of times (most recently in the Kikizo thread) and I really want to emphasize that I believe 360 *would* be capable of that - it's simply that Kojima is a superior dev as to why we haven't seen any trailers like that for 360 yet (and some would say GoW is better anyway). Right now Kojima simply cannot be making efficient use of the Cell and other hardware; I don't see where the XeCPU couldn't keep up.

It'll be MGS5 or something where PS3 really begins to pull away. So though I'm not putting a stake in the ground in terms of 'Killzone visuals' or even MGS4 trailer achievement, I do think that for the most part first-gen PS3 games will be similar to their 360 contemporaries at the time, though even a moderate increase in physics and such would put them ahead in many peoples opinion. But it's the future we should be most excited about.

I expect the third generation of PS3 titles will really shine, the first engine that is really SPU centric and just treats the PPU as a coprocessor is going to kick arse. The SPUs are fast like greased lightning but just require a different paradigm thats not going to be fully incorporated for a few generations…

[Sephiroth_VII]

Yup, sounds like the final kit. Especially if they have the complete OS onboard.

An OS taking up around 150 MB(estimate)... Linux? If not, it sure isn't XMB, since the PSP is running that, with only 33 MB of system memory.

[Heinrich4]

They must have the final kit (if BD in the devkit = final kit). So this must be some kinda offhand confirmation of what development kit they have :D

I want know how it looks RSX ... is a G70 like or going to G71 way...

[Heinrich4]

Yup, sounds like the final kit. Especially if they have the complete OS onboard.

An OS taking up around 150 MB(estimate)... Linux? If not, it sure isn't XMB, since the PSP is running that, with only 33 MB of system memory.

But x360 uses something like 32MB for this , its possible an M$ product uses less MBs than "unix universe like " on ps3 ?

[overclocked]

Should be fun and interesting to see that difference as it evolves.

[BlueTsunami]

About the memory and the OS, I fully expect to be the physical OS of the PS3 (the one thats on the system out of the box) to be much more feature rich than the PSP.

The PSP to me is XMB in its basic form. The PS3 version should be handling a whole lot functions. How this will differ from the "Blade" interface that the 360 has, i'm not to sure. If the PS3's OS is about 2x bigger than the Xbox360s OS it makes me wonder how feature rich the OS actually is...

[VG Aficionado]

An OS taking up around 150 MB(estimate)... Linux? If not, it sure isn't XMB, since the PSP is running that, with only 33 MB of system memory.Do you honestly believe a games console will be using an OS which needs around 150 MB of RAM for itself out of 256 MB (main RAM)? It's not a Windows PC! cpiasminc mentioned a while ago that 360's OS needed 32MB of RAM permanently. I expect PS3's OS to need as much space or maybe less than that.

I believe PSP was originally intended to contain 8MB of main RAM and most of it should be needed for game code and content, so guess how much RAM PSP OS needs during gameplay.

[xbdestroya]

It is possible that PS3's OS could simply be more bloated than 360's, as counter-intuitive as that sounds. Still though, MS is the more experienced OS developer. Not that I think this, I'm just putting it out there as a possibility.

But anyway I'm pretty sure it's not Linux he's refering to, and it's going to be *well* lower than 150MB if I had to venture a guess.

[Sephiroth_VII]

The 150 mb of course represents the amount the OS takes up in the RAM. It can't be Linux, since it seems that he's talking about the standard OS. Could it be the MGS4 OS, we saw in the trailer?

[xbdestroya]

Yeah but 150MB is just way too big. I'd expect it to be below 50MB for sure.

[Crossbar]

32 MB would be more than enough for Linux.
We are not talking about any bloated desktop distro.

I think a lean and mean Linux version with the required Cell adaptations and some playstation tweaks would be quite possible.

[xbdestroya]

32 MB would be more than enough for Linux.
We are not talking about any bloated desktop distro.

I think a lean and mean Linux version with the required Cell adaptations and some playstation tweaks would be quite possible.

So you think it's possible that Linux might ship as the embedded OS, sans hard drive? I mean it's certainly possible. I myself would expect something much different - and akin to the PSP's - for the boot OS though, and everything else to run on top of that.

[cpiasminc]

I believe PSP was originally intended to contain 8MB of main RAM and most of it should be needed for game code and content, so guess how much RAM PSP OS needs during gameplay.
As it so happens, the PSP OS reserves exactly 8 MB during gameplay. Though it actually probably *requires* less than that.

32 MB would be more than enough for Linux.
A Linux kernel without any sort of GUI subsystem or window manager running can easily run within 8 MB of RAM. A lightweight RTOS kernel like QNX can be even smaller (down around 1 MB). Now when running the actual frontend, running an Xserver and client, running a window manager and what not, it could take up a whole lot more (and yeah 50-100 MB is reasonable), but as long as those things are disabled while a game is active.

Part of the reason 360's OS is eating up 32 MB or PSP's OS eating up 8 MB is simply that the GUI is always active. PSP games, for instance, are required to allow you to step out using the home button and go to your menus. 360 developers get some tools based on the dashboard and Live, (e.g., a game can offer dashboard skins), so those components need always be active.

[Metal Sphere]

XB, it might interest you to know that someone over on B3D apparently let it slip that the OS is 64 MB. I'll link you guys to where this was found out in a second.

It also looks like they may have the final kit, and like previously said, if they don't it sure makes a strong case for it. However, weren't they waiting for AACS troubles to be resolved before making the drives?

Edit: Here's the link

http://www.ga-forum.com/showthread.php?t=86399&page=1

Apparently Shifty over on B3D let slip the 64MB bit that apparently shouldn't have been said.

[xbdestroya]

Edit: Here's the link

http://www.ga-forum.com/showthread.php?t=86399&page=1

Apparently Shifty over on B3D let slip the 64MB bit that apparently shouldn't have been said.


Shifty didn't 'let slip' anything though; that was just a guess on his part. FYI he's not a dev either. :)

By the way here's the link to his actual post, I'm sure you'll find it much less provocative than whatever's on GAF: http://www.beyond3d.com/forum/showpost.php?p=698776&postcount=12

[BlueTsunami]

Apparently Shifty over on B3D let slip the 64MB bit that apparently shouldn't have been said.

I just read through this same thread version over at B3D and it seems as though Shifty is more or less guessing at the size of the Memory Footprint for the PS3's OS, nothing definitive.

[Metal Sphere]

And yet he quickly edited his old response of 64MB stating he wasn't sure that was supposed to be said. I'm sure you'd do the same if you were under an NDA and screwed up a little.

[BlueTsunami]

And yet he quickly edited his old response of 64MB stating he wasn't sure that was supposed to be said. I'm sure you'd do the same if you were under an NDA and screwed up a little.

I wasn't aware that Shifty was under any NDA's? I thought he was in the same boat as all of us (when it comes to information about the PS3). Just an observer waiting on pins and needles for some new info.

[xbdestroya]

And yet he quickly edited his old response of 64MB stating he wasn't sure that was supposed to be said. I'm sure you'd do the same if you were under an NDA and screwed up a little.

Metal Sphere Shifty's not a dev - he's not under NDA. I mean if you like I can ask him for you in that thread to help set things straight across the net. :)

[Metal Sphere]

Sure thing, heck quote it and have BT post it over on GAF. Thanks for setting things straight BTW.

[cpiasminc]

Also, it's possible that it's more on the devkit than on the real machine. For instance, you've got double the RAM on the PSP devkit than on the actual PSP, but the thing is that the upper 32 MB's address space is mirrored to the lower 32 MB, so the OS ends up reserving its 8 MB twice when you run in 64 MB mode.

[Metal Sphere]

So it makes the 8 MB a "sizeable" chunk when it reality it's far from it if I'm understanding this right.

[BlueTsunami]

Also, it's possible that it's more on the devkit than on the real machine. For instance, you've got double the RAM on the PSP devkit than on the actual PSP, but the thing is that the upper 32 MB's address space is mirrored to the lower 32 MB, so the OS ends up reserving its 8 MB twice when you run in 64 MB mode.

This is what I was wondering (if the Memory Footprint on the Devkit =! the Footprint on the actual PS3).

[Crossbar]

So you think it's possible that Linux might ship as the embedded OS, sans hard drive? I mean it's certainly possible. I myself would expect something much different - and akin to the PSP's - for the boot OS though, and everything else to run on top of that.Though it would be possible. Giving it a second thought, there are probably few benefits to have games running on a tweaked Linux kernel. PS3 will likely have an inhouse developed microkernal with a GUI ontop.

Linux would be nice for running a web browser or some other application but games, no.
However, they may run linux on top of the same micro kernel, when not playing games.

[cpiasminc]

So it makes the 8 MB a "sizeable" chunk when it reality it's far from it if I'm understanding this right.
Well, no, I was just saying that the chunk could be worse on the devkit and people could confuse the footprint on the devkit for the footprint on the retail unit. 8 MB out of 32 is still a pretty serious chunk for the PSP, but if I said that PSP's OS reserves 16 MB (which is true on the devkit), people might think that only half the RAM on their PSPs is usable. A hypothetical 48-64 MB on the devkit could mean 24-32 on the actual unit. And 24-32 out of 256 MB main RAM is also a lot, but it's at least better than the idea that it is 48-64 out of 256.

That's also leaving out the possibilty that other resident programs like a profiler or something similar may eat up memory on the devkit while you're using it, but that's a different issue than the OS.

[frosty]

Man, everyone is starving for info, yesterday the boards were dead, now they are quite busy.... Feed us Sony!

[koldfuzion]

amen frosty. All we're left with is how much ram the dashboard/OS will hog or not. Man we're really searching for kernels. haha :P

[Crossbar]

FYI: Deano is online on B3D right now giving some more info.

[xbdestroya]

Alright Metal Sphere this is for you. :smoke:

Take it henceforth to whatever these forums are that bring you to say such things.

Ha ha ha ha ha! Just goes to show what a load of crap people post on internet forums!
I'm not a console dev. I'm a degree graduate programmer who writes (cumbersome) high-level PC code, and hopefully I won't be doing this job forever as there's other things I'd much rather be doing.

It's painfully obvious I'm not a console dev; have you ever heard of a dev even half as verbose as me?! They're too busy working!

http://www.beyond3d.com/forum/showpost.php?p=699126&postcount=46

[DeanoC]

So when did I become Deano of Beyond3D... I've been around here for quite some time as well (long before it changed to this new version, though only created an account fairly recently...).

[rog27]

So when did I become Deano of Beyond3D... I've been around here for quite some time as well (long before it changed to this new version, though only created an account fairly recently...).

Bah...He's everywhere! ;)

[xbdestroya]

So when did I become Deano of Beyond3D... I've been around here for quite some time as well (long before it changed to this new version, though only created an account fairly recently...).

Deano! Well I must say it's a first post in your classic wry style. http://community.the-underdogs.org/smiley/happy/wink4.gif

Since we're in a more laid back setting here, I'll go ahead and ask if indeed you guys are on 'final' kits with Blu-ray or on bridge kits without. Didn't want to change the topic in that other thread more than I already had. Of course I understand if you can't answer that, but thought I might as well ask it since some have been wondering ever since Barbarian made his dev kit allusions confirming RSX.

[DeanoC]

lol xbdestroya direct and to the point...

When Sony feel like publically talking about new hardware, then I'll happily add some comments until then, no comment.

[BlueTsunami]

So when did I become Deano of Beyond3D... I've been around here for quite some time as well (long before it changed to this new version, though only created an account fairly recently...).

:p

Hey! I tried changing the title to Deano of Ninja Theory! I'm surprised to see you here (even more surprised that you've been hear before the site change)

[xbdestroya]

Well, nAo Panajev and a whole mess of people used to be here before the changeover to the new... face? Format? Don't know what to call it. But there was like a period of several months in Jan-March of early 2005 that the forums were just down completely. I mean I certainly didn't know if the forums would ever come back up myself (just a normal user back then). That was a weird time, not knowing why PS3Insider (it's original name) disappeared, or if it was ever coming back.

It certainly is a pleasant surprise to catch you here though Deano.

[Sephiroth_VII]

Those days were terrible. Everyone left the forums. At worst, I think we had 2 members visiting daily. Without E-mpire, PSINext would've died.

Xb, do you remember the day, when we first saw:
http://img.photobucket.com/albums/v604/Sephiroth_VII/MatrixSystemFailure.jpg
I do. After a few weeks of confused members and staff, Andrew announced that he was moving on with his life.
But, lets stop thinking about the past, and start discussing the future: PS3.

[xbdestroya]

lol xbdestroya direct and to the point...

When Sony feel like publically talking about new hardware, then I'll happily add some comments until then, no comment.

LOL, well just thought I would ask about it to get it out of the way.

Anyway I thought your blog entry was interesting in a couple of ways, but one of the aspects that stood out for me was the mention of giving the team hard limits on the memory footprint they had to work with. I think that sort of forthought is a great step, but it also just made me think of the team dynamic in general.

With the sort of rollercoaster ride Ninja Theory and Heavenly Sword have had, would you say the team dynamic has changed at all from when you started to now? Several platform changes and many new team additions later...

[BlueTsunami]

Well, nAo Panajev and a whole mess of people used to be here before the changeover to the new... face?

Wow...I didn't know so many people that i've seen through B3D and GAF post here (nAo @ B3D, Panajev on GAF..then I noticed him on B3D and now come to find out that Deano used to post here)....

Its a small internet world....

[xbdestroya]

Well, I don't think Deano posted here in the past - I think he was saying he used to browse. Yeah those were good days though - very much a technical forum back when Cell patents and speculation were all you had - which is a spirit a lot of us still cling to.

But I agree - it *is* a small Internet world. And Sephiroth I do remember seeing that first 'page cannot be displayed' error; it's a strange feeling when you realize how ephemeral everything on the Internet truly is.

PS - By the way Panajev is awesome, he helped fill in some of the holes in that 'Sony Fab Audit' thread I started, and ultimately is the source of where the confirmation of 200mm wafers on the existing 90nm processes and the process designator names came from. Thought I'd give him some credit for that, even though he didn't post directly.

[CreativeWriter]

Though it would be possible. Giving it a second thought, there are probably few benefits to have games running on a tweaked Linux kernel. PS3 will likely have an inhouse developed microkernal with a GUI ontop.

Linux would be nice for running a web browser or some other application but games, no.
However, they may run linux on top of the same micro kernel, when not playing games.

Isn't the whole idea of dual HDMI output to be able to surf the net while playing games? Would devs need to set aside the eventual RAM needed for that contingency (even if few people will be running that set up at launch)? Would we need to run Linux as a background OS to allow that possibility? If these are silly questions tell me. I'm just starting to catch on with the tech talk...

[frosty]

Not silly at all, actually it makes perfect sense, although I'm not the most technically mided of us here either.

[venomv]

If that happens they would need to set aside a good chunk of RAM, but I have seen nothing about it except a little baseless speculation.

[frosty]

baseless speculation? sony mentioned it themselves at the e3 conference!

[BlueTsunami]

Well, the Memory Footprint for the OS reserved in RAM could probably encompass a browser that can be reached at any point during gameplay. I'm thiknking in terms of how the Dashboard in the 360 is reached.

[Crossbar]

Well, the Memory Footprint for the OS reserved in RAM could probably encompass a browser that can be reached at any point during gameplay. I'm thiknking in terms of how the Dashboard in the 360 is reached.I guess you are not talking about a full blown browser like Internet explorer or Firefox, because those will likely break any memory boundaries after opening a few extra windows with random applets and such. I doubt it will be possible to use a general purpose browser during game play, maybe some limited Sony "HUB" functionality with game chats and similar, I guess the 360 dashboard is just about that.

I do not rule out that they may provide a full blown browser running under Linux (not during gameplay), but that will likely require a hard drive and therefore not be a standard feature unless a HDD will be standard on all consoles. I myself doubt the rumours that HDD will be standard.

[BlueTsunami]

I guess you are not talking about a full blown browser like Internet explorer or Firefox, because those will likely break any memory boundaries after opening a few extra windows with random applets and such.

Possibly something extremley simple. Nothing that is very bloated or feature rich. Just a standard browser that would be use to check out web pages quickly, not to really sit down and browse around (as you would if the game wasn't on and you were in the physical Linux OS).

[Crossbar]

Possibly something extremley simple. Nothing that is very bloated or feature rich. Just a standard browser that would be use to check out web pages quickly, not to really sit down and browse around (as you would if the game wasn't on and you were in the physical Linux OS).
I don't want to sound too negative, but I don't think people will be happy with a crippled web browser. People may just get annoyed when they can't see the same web pages as in a ordinary browser.

Maybe the PS3 could provide a function to swap the memory image of the game to the HDD and then swap it back when you are done browsing, but I am not sure it is even possible, I think the internal state of the Cell is the hardest part to swap back and forth.

[VG Aficionado]

I wonder if they just said that there could be games that allowed the player to play and browse / instantmessaging / email / whatever at the same time on two different screens, not that it would be a mandatory feature for every single game.

Honestly, I don't see that happening as a general trend. One thing is saying what PS3 could be capable of doing, and a very different thing is whether it would always be practical or its resources should be used for more important things during gameplay for most games. I don't expect many games to support double video output simply because most people won't use that feature and Sony knows that (I remember people's mixture of awe and laughs at E3 when they were mentioning that possibility for the first time), even if they would like gamers take advantage of that possibility. While Sony may not care about losing money on every sold console for the sake of including state-of-the-art hardware, I'd find it hard to believe they'd want all games (PS3's main application) to be more limited by adding mandatory features most people won't be using, even if they think there could be an small portion of gamers that would do so.

In the event these were mandatory and became widely useless, I wonder if they would release a firmware update to allow a more efficient use of the main RAM while cutting the browser/email/etc. feature during gameplay. It could cause some complaints, but the benefit would be worth it for future games.

Yeah, I'm guessing too much. I must be tired of this lack of news and info.

[warmachine]

I didn't want to open a new thread, so I just upped this one. ^^

Deano has a new blogentry (http://rattie.demon.co.uk/?p=49) with a rather confusing detail in it.


[...]
Big mainstream games at the moment aren’t fun to work on… We are so stuck doing the non important stuff (1000 facial mocaps and shaders on 10 processors with actors and cameramen straight out of hollywood…) that the actual process of making the important bit (the gameplay) has becomes nasty…
[...]


What does this mean?
What are those 10 processors refering to? (Cell, RSX [because of shaders])

Can somebody clear this up, please?

[Hrama]

I think it was just a bit of exageration on his part to get his point across on how bad things are getting, could be wrong though.

[Crossbar]

I didn't want to open a new thread, so I just upped this one. ^^

Deano has a new blogentry (http://rattie.demon.co.uk/?p=49) with a rather confusing detail in it.

What does this mean?
What are those 10 processors refering to? (Cell, RSX [because of shaders])

Can somebody clear this up, please?
Yeah I remember reading that entry, i think it was posted the day after devstation, made me think if Deano did not go there, maybe he didn't need to. The entry was really negative, he was obviously not very happy with his current work situation, they are probably under a lot of stress, which he thinks is kind of status quo in his trade.

The reference to processors may just mean they have something like ten artists working with shader design software to create the shaders for the different characters. I don't know, but I don't think it is any important information.

[xbdestroya]

Ten processors could also refer to the ten 'logical' threads of Cell (when the PPE is taken into account). I haven't read the entry yet though, so I don't have the context to base that comment on. I'll get to reading it when I can though, just been busy this last week.

[cpiasminc]

Sounds like he's talking about the content creation phase which can potentially use any old machine or cluster of machines, not necessarily a console.