Benchmarking The Ubuntu "Low-Jitter" Linux Kernel

[liam]

Sidicas is on the right track. Later poster is completely wrong.

Indeed it should be easy to understand, that if kernel blocks for 5ms, rather than 0.2ms, timing jitter is going to be present, and alter framejitter, and also 5ms lost of 20ms, to calculate frame.

Peace Be With You.

Assuming I am the "later poster" could you please tell me how I am completely wrong?
It could be a language issue but I don't understand how you fail to grasp that RT adds overhead. Yes, less jitter (i.e. smoother frame rates), but you also lose the ability to run for periods of uninterrupted time on the cpu, which is sometimes necessary in order for a frame to be completed. Now, I could see a setup where you prioritized frame completion and delivery (that is, it responds to the irqs from the gpu before almost anything else) over everything else but that would mean, necessarily, that you'd have a less responsive system since inputs would then be delayed. That kinda defeats the point.
Setting up a RT machine requires a lot of thought.

[liam]

Why is gamer2k posting in this thread? To be an example of how much babble can be done, that is not according to simple observation? "It spends time calculating preemption". LOL. The benchmarking even shows some higher numbers, and no other are below 1fps difference. What you do OBSERVE though, is a game that was choppy (low GRAPHICS throughput) to one that runs smoothly at 72fps. HIGHER throughput, when using preemption with graphics. Again, we do not care about theoretical numbers, that say nothing about what is ACTUALLY happening on screen, relating to USER experience. I really hate people who are that far removed from reality.

Peace Be With You.

I'm sorry, but you are just wrong.
Michael benchmarks throughput fine and your kernel didn't perform any of these miracles you're talking about. We've seen his numbers, and they confirm what we know from theory: low latency doesn't increase throughput (in this context, FPS).
You can have a choppy game but still high throughput (since it is an average). For simple scenes, and low kernel contention, you might generate a hundred frames in less than a second but other times when there is more gpu kernel communication, or more kernel contention, you might only manage 20 fps. So, over long periods that can average out to high fps but extreme jitter.
Does that not make sense to you?

[Paradox Uncreated]

Where the hell does these idiots come from. A whole tread with explanations, and sane thinking. And yet they don`t understand? Go and complain to Intel who makes the CPUs I like." reduce latency from low microseconds to tens of nanosecond "

Finally I have have my transparent os, with 0.2ms max jitter. If that doesn't appeal to you, instant sound, accurate FPS, low latency internet, well then. You should buy some kind of framereducer. I mean seeing how much ignorance there is online, it will probably be a big hit. Finally you can get those 5 choppy frames. Some kind of LCD feature, so ofcourse the "throughput" still goes on behind.

What a bunch of perplexingly stupid loosers. Anyway I am having a good time, and thought I'd share it. But ofcourse there are those who serve the firespirit satan, and denounce all that is good.

Peace Be With You.

[liam]

Where the hell does these idiots come from. A whole tread with explanations, and sane thinking. And yet they don`t understand? Go and complain to Intel who makes the CPUs I like." reduce latency from low microseconds to tens of nanosecond "

Finally I have have my transparent os, with 0.2ms max jitter. If that doesn't appeal to you, instant sound, accurate FPS, low latency internet, well then. You should buy some kind of framereducer. I mean seeing how much ignorance there is online, it will probably be a big hit. Finally you can get those 5 choppy frames. Some kind of LCD feature, so ofcourse the "throughput" still goes on behind.

What a bunch of perplexingly stupid loosers. Anyway I am having a good time, and thought I'd share it. But ofcourse there are those who serve the firespirit satan, and denounce all that is good.

Peace Be With You.

I love the substantive responses of four year olds.
I truly hope you are a troll and not the zealot you seem to be (seriously, "Peace Be With You" and yet you make the most disgusting statements preceding it...I'd imagine God would be pissed, if not for hypocrisy but at least blatant inconsistency).
Ugh, mixing OS discussions with religious imagery (and seeming statements about morality).

[Paradox Uncreated]

I love the substantive responses of four year olds.
I truly hope you are a troll and not the zealot you seem to be (seriously, "Peace Be With You" and yet you make the most disgusting statements preceding it...I'd imagine God would be pissed, if not for hypocrisy but at least blatant inconsistency).
Ugh, mixing OS discussions with religious imagery (and seeming statements about morality).

God is actually quite pleased. He is not some alien concept to human nature, but infact is human nature itself. If I am pleased, God is pleased. And GOD finds you to be a provocative idiot. And no doubt does those who know you personally aswell. That is Gods opinion of you, and if you look inside, you will find that opinion there aswell. These things doesn`t exist in isolated moments online. How dumb where not just you. Again the pretensious, and feeble mind of the idolater, not understanding sense, going against brilliance, (and the praises of God) and associating idiocy with God, as if HE, the retard, knew God better. The very faithless in a nutshell.

Peace Be With You. (and that is a standard greeting. if you are fuckwit, well maybe it isn`t so much for you, as you obviously lack the capacity to understand it anyway.)

btw: Here is my research on God. http://paradoxuncreated.com/Blog/wordpress/?page_id=62 Because truly research by a brillianrt individual is a blessing, and does the faithless ever make up idiocy, believing victory lies with feebleness.

And when you see people like this making up and being complete idiots, you can understand why blasphemy was a big sin, and punished by death, because ultimately that is what they are going to claim. Unfortunately if idiot constructs, based on hadithism or trinitiy, instead blasphemy becomes a reverse concept, in their favour. And that is again why association with God is so bad, and what originally blasphemy is. When idiots uphold fantasy-concepts and claim they are related to God, and fight for them, and make laws according to them. Trash-idiocy of people with garbage-abilities was ever the only enemy.

[Paradox Uncreated]

It`s unbelievable. Through the entire thread these people behave as if there is something wrong with low-jitter/low-latency, ignoring the benchmark showing higher numbers in some benchmarks, and ignoring the fact that benchmarks without preemption suffer from high jitter/latency, and have less actual frames displayed on screen. And now undoubtedly they are going to disagree with sane religion.

That really says alot about who they are. I don`t know how these people think they have an audience online, or why they think their arguments is going to matter. Like I said elsewhere, it`s like a cottaging-activist trying to talk morality to a religious man. And that is so true, as ultimately feebleness is a satanic attack on self, satan is a lustcultivator, and long time upholding satanic concepts, is to removeoneself from humanity, and that is what a cottagingdefender has done aswell. And I am indeed a very religious person. However many today also has that concept wrong. The ultimate praises of God, in truth and honesty, though, is ofcourse in no conflict, with your highest hopes, and most brilliant insights.

Peace Be With You.

[Paradox Uncreated]

And maybe that is the most important thing you can learn from this entire thread. Lowlatency/lowjitter is going to happen regardless. I just do it early.

That the ultimate fuckwit activity is to claim senseless things about God. And that is why there is war in the world. So now you know the level of their stupidity.

Imagine the billions that could go to care of humanity instead of wars and suffering.

So then you know who satan is, a simple man upholding fantasyconcepts, who in turn in nothing other than obsessing about his genitals.

And when you see gay obsessing about sex, you know who they are too. And it would not surprise me if Liam (& co) told us he was "gay".

Peace Be With You.

[Kano]

Your best optimized kernel does not help when the gfx card or the cpu is too slow. When you enable vsync and the the rate goes down from 60 to 30 then it is definitely no kernel problem. When you manage to get 60 fps then the kernel is really unimportant.

[Paradox Uncreated]

The fuckwits will babble on. This is not about turning off Vsync. This is about accurate low-jitter FPS. Which apparently is real hard for many to understand. I am just happy God has graced me with intelligence, to pursue my own happiness in life. And that is what I will do. Regadless of people who obviously don`t have the senses to react on jitter, what someone else here compared to braindamage, or seisures. Indeed nobody would want to be the guy with jittering eyes.

Now this subject has been talked to death, and reached even the logical extreme in religion. So no further comment should be neccesary. I can update the thread when I get the new low-latency h/w though, and give my view on that.

Peace Be With You.

[ninez]

I love the substantive responses of four year olds.
I truly hope you are a troll and not the zealot you seem to be (seriously, "Peace Be With You" and yet you make the most disgusting statements preceding it...I'd imagine God would be pissed, if not for hypocrisy but at least blatant inconsistency).
Ugh, mixing OS discussions with religious imagery (and seeming statements about morality).

He is both a zealot and a troll. ~ For one, he is Norwegian and a convert to Islam, and even has gone so far to now use an alias (islamic name) rather than the name he was given by his parents. He is the only person i know of that has "PRAISED BE GOD" written in the README's for his crappy plugins - which is odd to say the least. He's heretic even in his own faith (proven to be in another thread), he's just lucky he's a convert and not living in an islamic state.

And by the way, Liam is most certainly correct -> RT can affect throughput negatively, this is a well documented FACT.

I find it laughable that in the other thread (where PU and i got into an argument) he claimed that his 'low-jitter' kernel essentially made RT useless/not needed anymore, yet now a week or so later he plans to be his kernel using the RT patchset. lol. Even funnier, him posting on the rt-user-list;

I think it complains about not finding rootdevice. Anyway, I am getting a new machine, so it might not be much of an issue. If you still want to try and find the bug let me know. Also how do I compile without threadirqs, if I enable basic-rt, threadirqs are enabled in .config also.

Hey dumbass, did it not occur to you that the reason it enables threadirqs is because RT requires it? (your fucking dumb). After all, threadirqs while (now) mainline were originally a part of the RT patchset (merged into mainline in 2.6.39) and are a requirement. You should also learn how to configure your system, your root device problem is likely human error / bad config - ie: you weren't paying attention... I've got 3.6.3-rt6 installed and running no problem (although i use 3.4-rt since 3.6.3-rt is buggy, for now). I for one wouldn't put any stock into this wannabe kernel developer, who doesn't seem to know what he is doing, at all. Another funny example of PU stupidity;

PU: Yes, it works fine without basic-rt, or full-rt. Do you know if basic-rt can
be compiled without threadirqs?

Tglx: No. And that's not interesting at all. We really want to know what's going wrong when you have irq threading enabled. You can also try the following. Compile the kernel without RT and add "threadirqs" on the kernel command line. So that's just mainline + irq threading. Does that work? In any case it would be helpful if you provide the full dmesg output of a failing boot.

PU: Ok, you really want to know. Well I can do anything to help you with that. Does dmseg contain info from last boot? Or can it be accessed from the console-thingy?

So aside from not knowing all that much about the linux kernel, apparently PU doesn't even know about logging in linux either... Nor does he actually provide any of the information Tglx is asking for (just like he provides no metrics to support is kernel being as great as he says).

I can only speak for myself - but I think you would have to be a complete moron to put any stock in PU's 'low-jitter' kernel. It's pretty obvious he is just an enthusiast, hacking (more like fumbling) around but not really knowing what he is doing. it's laughable shit really.