Benchmarking The Ubuntu "Low-Jitter" Linux Kernel

[Paradox Ethereal]

I have now moved to OpenBSD, and the 3-clause BSD licence. Please also see my channel here for more about me: https://www.youtube.com/channel/UCR3...able_polymer=1

[Paradox Ethereal]

https://lkml.org/lkml/2017/10/29/105

> I really believe in this, and what makes this just perfect: Everyone
> is their own newsservice, getting their views on for instance,
> youtube. And gets the income from this. Which makes a finely
> granulated internet economy.
>
> A test channel: https://www.youtube.com/channel/UCR3...S5A702wo4bol_Q
>
> Peace,
> Ywe Cærlyn.
>
With Linus Torvalds as patchmeister as usual, ofcourse.

[Paradox Ethereal]

Hi. Michael, are you reading this? Could you change my username to Paradox Ethereal.

Btw, I have come a long way since this, and ultimately took a wide philosophical requantization on the linux environment.

Philosophical requantization of a (atm) theoretical linux distribution:

Excellent Ubuntu, is a Good Linux, with a Minimal Jitter Kernel.
An Available Source Operating System.
Philosophical Lead: Ywe Cærlyn (me)

Desktop Flavour: Customized Gnome

Finetuned for fast reponsiveness, and smoothness in operation. Configuration of Kernel, for favoring short buffers, lowest latency, minimal jitter, minimal wasted CPU, max cpu utilization.

Perfect scaling, from desktop to supercomputing.

Redefined Internet, with the finest philosophy, and correct attitude.

Call 999-Excellence for a trial CD... No that we don´t have yet, but how does it sound?

Peace.

[Paradox Ethereal]

Perfect.

So as I said, I ordered a computer with components optimized for latency. An E5 workstation, which I installed a GTX660 in also. HexaCore. What can I say, I am very pleased with the results.

Peace Be With You.

[Paradox Ethereal]

Yes, then we have even seen numbers on low-jitter.

Summing up:

First of all, a kernel with "low latency desktop" enabled. You can edit Kconfig.hz and change 100 to 90. (search/replace).
You can add idle=poll and tick_skew=1 to boot options. And compile a shaved local kernel by doing "make localmodconfig" from a full distro kernel. (Also remember to turn of high_res_timers if enabled, because then hz will be 4016 or atleast high.)

CFS granularity should be set to 1158500nS. (Current setting is a bit high, and may give jitter)
Renice X to -20, to prevent X being a bottleneck.
Remove 60hz limit in doom 3, to avoid timing jitter. http://paradoxuncreated.com/tmp/AutoExec.cfg

Some nvidia-specific stuff on my blog aswell : http://paradoxuncreated.com/Blog/wordpress/?p=2268

A lot of people think SLAB has lower jitter than SLUB etc, aswell, and some tuning with regards to what kernel options execute the least code, least background activity can be done.

And then run your apps you want low-jitter in, reniced to -20. (doom 3, chromium-browser, wine (needs wine* + winappname*)

Peace Be With You.

[thofke]

This article measured jitter in the most false way possible. Maybe this is a better approach?

Frame latency analysis on Doom 3

[Paradox Ethereal]

Seems to be some posts that are disappearing? I can`t believe atleast 4-5 people are deleting their posts? I got this notification now: "I know what jitter is in electronics but kernels?" ?

Edit: I removed some posts aswell, due to my blog no longer being operative, so all those links are outdated.

Jitter in electronics is really the same thing. It`s timing jitter, division of clocks, waiting for delivery of signal. Ultimately the hardware sets the minmal jitter limit. Usually software systems, interrupt the software, with interrupts (drivers etc), preemption (context switching between multiple apps), daemons (mailcheckers, automounters, whatever) etc. And all this ultimately leads to clock-jitter on the overall system, which usually is called "Os-jiiter".

Peace Be With You.

[Paradox Ethereal]

Edit: outdated.

[Paradox Ethereal]

And hopefully the local dealer can get on my order, so I can get my low-jitter COMPUTER. Which again will ofcourse require a low-jitter kernel for maximal effect.

[Paradox Ethereal]

Have you seeneth him, whom playeth pacman?
And alleges you of jinxeth it.
He doth indeed hate low-jitter, and thinketh the blackmagic makes pac go the wrong way.