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Re:Desktop compositing latency is real by pjc50 on Tuesday November 21, 2017 @09:47AM (#15748124)
Solution: send the pixel to the screen over IP!

(joking, but with a tiny serious element)

Re:Desktop compositing latency is real by em3rgent0rdr on Tuesday November 21, 2017 @09:54AM (#15748178)
this reminds me of the argument that instead of going to USB C 3.1 as the grand unifying connector for all peripherals (including video), we should have instead migrated to Ethernet cables for everything.
Re:Desktop compositing latency is real by CodesInChaos on Tuesday November 21, 2017 @12:08PM (#15749415)
Currently ethernet doesn't look cheap enough for video to me.

Even a simple 1920x1080 60Hz monitor needs 3 Gb/s, a 2560*1440 144Hz monitor 13 Gb/s, a 4k 60Hz 12 Gb/s.

DisplayPort 1.2 offers 17 Gb/s and DisplayPort 1.3 offers 26 Gb/s.

Re:Desktop compositing latency is real by em3rgent0rdr on Wednesday November 22, 2017 @04:19AM (#15755474)
40 Gbps and 100 Gbps Ethernet standard was defined in 2010 [1]. Google "buy 100 Gbps Ethernet" and you will find it is real, although currently is geared primarily for datacenters.

[1] wikipedia.org/wiki/100_Gigabit_Ethernet

Re:Desktop compositing latency is real by frik on Tuesday November 21, 2017 @11:15AM (#15748864)
Actually not a bad idea. Ethernet speed is one gigabit per second.

And there are high throughput devices like LIDARs (eg Velodyne LiDAR known from Google/Waymo self-driving cars) that are connected via Ethernet rather than USB.

Having 1 GBit Ethernet LAN network since 2004, I would prefer the possibility to upgrade to 10Gbit home Ethernet in near future.

Re:Desktop compositing latency is real by astrodust on Tuesday November 21, 2017 @12:46PM (#15749849)
It's a terrible idea. USB-3 is faster than 1Gbit/s. and there's no way you can drive a 5K monitor with any current or near future Ethernet standard, the bandwidth demands are too punishing.

Ethernet isn't optimized around short-haul signals, like computer to screen over a few metres at most, it's for 100m+ runs in datacentres. The signals have to be a lot more durable.

Re:Desktop compositing latency is real by em3rgent0rdr on Tuesday November 21, 2017 @04:26PM (#15751729)
> "USB-3 is faster than 1Gbit/s"

But Cat 6 Ethernet is 10 Gbit/s.

Re:Desktop compositing latency is real by astrodust on Saturday November 25, 2017 @01:58PM (#15777305)
Still not as fast as USB-3+Thunderbolt which is already 40Gbit/s and intended to be pushed to at least 80Gbit/s to support 8K screens.
Re:Desktop compositing latency is real by wereHamster on Tuesday November 21, 2017 @04:50PM (#15751937)
> there's no way you can drive a 5K monitor with any current or near future Ethernet standard, the bandwidth demands are too punishing.

Really? You need more than 100gbit for 5k monitor? Because there is an 40/100gbit ethernet phy standard right now (has been for a while, since 2011). And work is being done on up to 200gbit (due to be ratified in late 2018).

Re:Desktop compositing latency is real by Retric on Wednesday November 22, 2017 @11:37AM (#15758135)
5120 * 2880 * 32bits * 60FPS is only 28.3 Gbit and both 40Gbit and 100Gbit are well established standards.

Granted 40GB cards are running 50$ and 100Gbit cards are running ~700$, but that's most from the low volumes involved.

Really though the larger issue is Ethernet connectors are not designed to be plugged in and removed regularly.

Re:Desktop compositing latency is real by em3rgent0rdr on Wednesday November 22, 2017 @05:37PM (#15761304)
> "Ethernet connectors are not designed to be plugged in and removed regularly"

Well could easily use a smaller and easier plug while still being pin compatible with ethernet.

Re:Desktop compositing latency is real by solotronics on Tuesday November 21, 2017 @09:57AM (#15748210)
ethernet over multimode fiber, I want to be able to have accessories hundreds of meters away from my computer
Re:Desktop compositing latency is real by willglynn on Tuesday November 21, 2017 @11:40AM (#15749135)
Careful, multi-mode fiber is near its scaling limits. 10GBASE-SR and 25GBASE-SR exist, but that's about it. (By contrast, 40GBASE-LR and 100GBASE-LR work over single-mode fiber, and DWDM + coherent optics can push the medium much further.) Wouldn't want to be stuck at 25 gbps forever ;-)
Re:Desktop compositing latency is real by makapuf on Tuesday November 21, 2017 @12:00PM (#15749326)
Yeah, some of us can type pretty fast. And for mice, some of us take clicker games seriously.
Re:Desktop compositing latency is real by OnACoffeeBreak on Tuesday November 21, 2017 @10:13AM (#15748332)
Just make sure those cables are never bent beyond the minimum bend radius.
Re:Desktop compositing latency is real by kpwagner on Tuesday November 21, 2017 @12:37PM (#15749713)
It's amazing how much you can bend fiber. Fiber is really hard to break just by bending it, assuming it is well insulated. You can have performance loss with bends and kinks though.
Re:Desktop compositing latency is real by nimish on Tuesday November 21, 2017 @06:38PM (#15752774)
Just use bend-insensitive fiber. It's not like copper cables like being kinked, either.
Re:Desktop compositing latency is real by dilap on Tuesday November 21, 2017 @10:15AM (#15748358)
in all seriousness, why not?
Re:Desktop compositing latency is real by lmm on Tuesday November 21, 2017 @10:21AM (#15748406)
The little plastic bits always snap off. Ethernet is great for semipermanent wires but not very good for peripherals like portable hard drives that are constantly disconnected and reconnected.
Re:Desktop compositing latency is real by jdietrich on Tuesday November 21, 2017 @10:42AM (#15748600)
That problem is largely solved if you use 8P8C connectors with a rubber boot protecting the latching tab.

https://info.pcboard.ca/wp-content/uploads/2017/04/RJ45-Conn...

Re:Desktop compositing latency is real by astrodust on Tuesday November 21, 2017 @12:47PM (#15749851)
You can't tell me that's better than the USB-C connector.

Even HDMI is better.

Re:Desktop compositing latency is real by robotresearcher on Tuesday November 21, 2017 @07:49PM (#15753207)
My MacBook Pro’s USB-C connectors glitch if you move them slightly. I like the data rate but I’m not happy with RAM-pack wobble in 2017.
Re:Desktop compositing latency is real by cpburns2009 on Tuesday November 21, 2017 @10:58AM (#15748719)
Even with the protective guard the little plastic tabs inevitably break on me. I can't even say those have fared any better than the unprotected versions.
Re:Desktop compositing latency is real by Groxx on Tuesday November 21, 2017 @03:17PM (#15751169)
My main complaint is that the protective rubber often gets stiff as it ages, which can make it pretty dang hard to remove old cables (until you resort to pliers).
Re:Desktop compositing latency is real by falcolas on Tuesday November 21, 2017 @11:13AM (#15748849)
Yeah, live hinges (that is, plastic bits that intentionally bend, not rotate on pins) are always going to break eventually. They're just so easy to make that it's a trade off that doesn't fall in the consumer's favor.
Re:Desktop compositing latency is real by mrob on Tuesday November 21, 2017 @01:12PM (#15750141)
Living hinges can have lifespan in the millions of cycles with the correct materials and design. I'm sure it's possible to make an Ethernet connector that doesn't break easily, but it would cost more, and people aren't willing to pay.
Re:Desktop compositing latency is real by jririr828283 on Tuesday November 21, 2017 @10:34AM (#15748532)
What’s that to do with displays which aren’t unplugged frequently?
Re:Desktop compositing latency is real by deathanatos on Tuesday November 21, 2017 @09:39PM (#15753770)
I plug/unplug from my display several times daily, since the MBP connected to it travels with me. Granted, the end of the cable in the monitor typically doesn't move¹

¹well, one of them. The crap LG monitors we have constantly forget about the peripherals that are attached, and one easy way to fix this is to detach/reattach the peripheral. I suspect that the company is never going to RMA these devices, sadly.

Re:Desktop compositing latency is real by lmm on Wednesday November 22, 2017 @03:41AM (#15755305)
USB-C is used for all sorts of devices many of which are unplugged frequently.
Re:Desktop compositing latency is real by 542458 on Tuesday November 21, 2017 @10:19AM (#15748401)
The obvious ones: Ethernet cables are big (imagine one on a phone), and aren't designed to be plugged and unplugged the massive number of times that USB cables are (spring contacts wear out, little clips break).
Re:Desktop compositing latency is real by em3rgent0rdr on Tuesday November 21, 2017 @11:09AM (#15748809)
well maybe the actual plug could be modified into a small form, while still being pin-compatible with cat 5/5e/6.
Re:Desktop compositing latency is real by jririr828283 on Tuesday November 21, 2017 @10:37AM (#15748561)
USB cables have little to do with the question of sending pixels via IP

Outside HDMI and some DisplayPort cables, all display connectors click or screw in

And we’re talking about desktop OS and displays

Re:Desktop compositing latency is real by digi_owl on Tuesday November 21, 2017 @03:48PM (#15751389)
I'm not even sure about sending it as IP, rather as raw Ethernet frames (or simply just using the cables).
Re:Desktop compositing latency is real by rasz on Wednesday November 22, 2017 @04:27AM (#15755506)
Some people tried, most went out of business. Either chapter 11 or bought for assets and IP. OnLive was the biggest one.