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Intel Developers Demo USB 3.0 Throughput On Linux
Sarah Sharp writes "Intel's Open Source Technology Center is working on USB 3.0 support for Linux. USB 3.0 has wire speeds of 5Gbps and promises to be 10 times faster than USB 2.0. A recent video demo shows speeds that are 3.5 times faster than USB 2.0. The USB 3.0 drivers will be submitted to the mainline kernel when the eXtensible host controller interface (xHCI) specification reaches a 1.0 release."
USB 2.0 gave us high-speed and full-speed. Some marketing department had to work really hard on the USB 3.0 specs, to come up with... super-speed.
Now let's talk about the obvious problem: at 5 Gbit/s, it's faster than the Ethernet in my house (1 Gbit/s). Am I the only one who didn't really notice a 10X speed improvement when moving from 100 Mbit Ethernet to gigabit Ethernet? Conventional hard drives are just too slow.
Maybe SSD + USB 3.0 would be really cool. Imagine a Flash based HD camera talking to a Flash based hard drive. Is 2009 the year of the Flash?
Which brings me back to my original point: for the next generation USB, I propose the name flash-speed :-)
PS: thanks to Intel for helping Linux stay on the leading edge. It looks like Linux may even support this before Windows, thanks to the Windows 7 schedule... I just wish Intel's pre-conditions on contributing to the xHCI specs didn't start with stuff like:
Step 1. Print and execute the xHCI Contributor agreement. Note: The agreement must be executed by a corporate officer.
--
http://fairsoftware.net/
Replace HDMI?
HD-resolution cameras, etc?
The next, even more expensive, version of the USRP?
Bruce Perens.
So, at this point USB 3 gives us speeds that 3-1/2 times faster than USB 2 in real world usage. Great! That's where plain old FireWire was in 1996.
... in the past, hormoned-up kids would have been foaming on about the non-technical aspects of the video.
Could you please explain that a bit?
It's my understanding that high throughput drivers usually use DMA.
In my experience polled mode drivers are pretty rare. Especially in high throughput.
Weaselmancer
rediculous.
Like any good slashdotter, I'm not reading the article until after I post. Is 3.0 still going to be heavy on the CPU? Really, the best thing they could do is take the good stuff from firewire and slap a USB logo on it. All the cheap stuff can continue to use 2.0, while the bandwidth intensive stuff in 3.0 can have their own controllers.
USB3 will make wire speeds faster, and devices more expensive, but it won't deliver the performance we need, because they haven't fixed the root issues. USB is a silly polling system where the host has to ask each device in the tree if it has anything to say, and then (if it's a "bulk" endpoint), allocate time and finally do the transfer (interrupt and iso endpoints have time allocated all the time). Unless they make fundamental changes (which they won't), USB will load up the host excessively and give disappointing performance. But at least with USB3, the price to add it to a device shouldn't be that much lower than FireWire, so we might see more people making the right choice for what to support.
yeah yeah, i read the comments about gigabit ethernet being faster, thats not the point, usb 3 is still better than usb 2, enjoy the weekend...
Politics is Treachery, Religion is Brainwashing
When can I buy my first motherboard that is USB 3.0 compliant? I want to build a rig in the spring. I'd consider holding off until the summer to get USB 3 so it is more future proof, but I won't wait another year.
http://blindscribblings.com - Tasty pop-culture in conceptual fashion.
USB suffers from 1 ms time quantization and thus latency. I see nothing about fixing this.
Example badness:
When running MIDI over USB, timing is forced onto 1 ms slots. Normally when playing a chord, the keys don't all hit at exactly the same moment. You can't really tell, except that this makes the music sound natural. With the 1 ms problem, the keys happen at exactly the same moment (bad) or spread out into two separate events (worse).
This shows where Linux is nowadays. It took literally years before USB1 was even supported and now Intel uses Linux to prove USB3's performance!
USB 1.1: Low-Speed and Full-Speed
USB 2.0: High-Speed
USB 3.0: Super-Speed
USB 4.0: Mega-Speed
USB 5.0: Ultra-Speed
USB 6.0: ???-Speed
Knowing Google's lust for data collection, the Soviet Union is still alive and well inside the psyche of Sergey Brin....
there's a girl in the video?
brb
Whenever a story about USB3 is written, the following caveats should be mandated by law if necessary:
1. Speed claims are theoretical, and do not reflect real-world results by a long shot. Lots of overhead, CPU dependence, etc.
USB2 promised 480Mbps and never delivered it. You get 250Mbps on a good day. Now we have marketing claims that USB3 will be "10x faster," yet a video demo shows it's 3.5x faster. That's 1.5Gbps, not 5Gbps.
2. Firewire 3200 is approved and on the way. It will be faster than USB3, backward-compatible with FW800 (same cables and ports) and should begin appearing on Macs in January. Firewire isn't dead; Firewire 400 is being eased out in favour of faster versions.
If FW 3200 performs like its predecessors, it should be (in real-world usage) routinely about 2x faster than USB3.
Moral of the story: don't settle for mediocre.
Well, I get high throughput with my NIC drivers that poll (I can't remember the kernel compile option for this ATM), but this is at the cost of a higher latency. The trade off is that I've got 5 NICs on this box and it turns out that without polling I get close to having an interrupt storm and spend all my time switching context to execute the drivers bottom half of the interrupt. With polling, the interrupt gets masked and I don't have to worry about servicing every interrupt coming down the line. My latency is higher, but I get more throughput for every time I service the bus as it has more packets to process. This also means I'm trading off space for time (I need larger ring buffers to queue packets) such that I have less memory for the system, but processes get more time on the processor between interrupts.
While not having to do with USB, the driver architect and concepts are likely very much the same.
If I mod you up, it doesn't necessarily mean I agree with what you've said, sorry.
An awful lot of people are looking down their noses at USB 3 because it's not Firewire. Has everyone forgotten that Firewire grants devices DMA access to physical memory? Any physically connected device can be used to bypass the system's security. I'm grateful that USB isn't more like Firewire.
Now where did I place that device that allows me to hit people on their foreheads over the Internet...
A good education is a bit like a STD - it makes you unsuitable for a lot of jobs and gives you a desire to spread it.
Wrong.
Weaselmancer
rediculous.
Comment removed based on user account deletion
Comment removed based on user account deletion
And what's the CPU usage of 3.0 going to be?
I know we all have cycles to spare in the multi-core universe, but I just view as bad design.
Wake me up when Firewire over UTP gets popular. THAT would be interesting.
The problem with expansion cards is that slots not plentiful on smaller towers and they don't provide front side ports. Not very convenient. Also, a USB 3 motherboard will probably give you 6-12 ports. If you plan on keeping your box for several years, more ports=better.
Why are they wasting everyone's time with USB 3.0, when the rest of the universe is shifting toward Ethernet as a common interconnect ? Note I didn't say IP, just Ethernet - good old CAT-5.
Frig, if the audio folks have already started that transition, then what the hell is Intel doing ? The audio industry is probably the most retarded in the world (according to my failed expectations), and even they see that Ethernet is a cost-effective and braindead simple replacement for all these proprietary cables we've had to contend with over the years.
-Billco, Fnarg.com
USB 9.9 WARP-SPEED / USB 10.00 ZPM boosted speed
but how much cpu time? and firewire should be able to faster with less usb load.
As it will be not just the speed but the cpu time / usb. Didn't PIO Mode 4 end up being slower then Multi-word DMA 0 and the high cpu use killed off pio 5 that showed up in a few bios back the mid 90's.
It'll still probably be noticeably inferior to FireWire 400 (IEEE1394a) when hooking up external HDs, etc.
My verdict: Meh.
It's a natural progression. I'm pretty sure that within the next few revisions USB will essentially turn into Firewire, much like (P)ATA somehow turned into SCSI (read SATA).
Once you start despising the jerks, you become one.
One thing that is at least as important for free software systems as speed increases is class compliance. Take audio and MIDI devices for example. Almost all USB 1.0 audio and MIDI devices are class compliant, and thus work reasonably well with the standard kernel module snd-usb-audio. But with USB 2.0 that changed for some reason - now many more devices require special drivers that often do not exist for Linux. It would be nice if Intel and friends could somehow push for more class compliant USB devices.
"Step 1. Print and execute the xHCI Contributor agreement. Note: The agreement must be executed by a corporate officer."
Those corporate officers have all the fun, executing this, executing that.
Shai Schticks:"You don't make peace with friends, you make peace with enemies"
Linux already has USB 2.0 support. So what? Try to find a USB voice dialup modem which will run on Linux - you won't find one. Back when modems were all serial port devices, support was near universal.
There's no point in having the USB 3.0 support if the device manufacturers will not produce device drivers for the platform.
Today with USB 2.0 you can get adapters that are "USB 2.0" and yet get only a tiny fraction of the spec's throughput. The basic problem with the USB spec is that there's no provision for ensuring that meeting the spec is achieved or even meaningful.
USB 3.0 demo shows [something completely different].
Business as usual?
If USB 3.0 is 3.5 times faster than USB 2.0, is that referring to the promised speed of 2.0 (480 Mb/s, unfortunately seen nowhere in the wild) or the more realistic speed (250 Mb/s, fine weather provided)?
In the latter case, USB 3.0 would still lag behind Firewire 800, let alone the upcoming FW 3200. ;-)
I'll wait and see and stick with fast and reliable FW in the meantime.
It is very nice to see that Intel is actively contributing to the Linux kernel, and especially on a device protocol.
Good. On. You!
Bah.
It's *Giga*watts.
It's pronounced as *Jigga*watts.
iNTEL paid shills timed this story submission to when a shill-load had mod points.
On the other hand, I just got a server issue trying to post this diatribe. Maybe the shills didn't have to time things.
iNTEL REALLY REALLY WANTS TO 0WN UR hRdwar3z
Is the maximum power for USB 3.0 still 500mA at 5V?