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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."
I guess for hard drives, the question is how close to eSATA it gets.
Also, does USB3 still have the CPU overhead and latency of earlier USB compared to FW?
John_Chalisque
That USED to be true. It's not the hard drive, all the layers that get put in between when you access a disk over the network. Modern hard drives can easily do 60MB/s sustained.
For instance, I have a couple raid6 arrays which clock in at about 250 MB/s and 150MB/s natively. If I hook that machine up directly to another machine's ethernet port I only get about 30MB/s sharing the device w/ iSCSI. SMB and NFS yield similar results. This is true even though I can get over 900Mbps using iperf.
Sharing disks over gig-e sucks when you actually need throughput. It's great for when you just need to expand a SAN and speed is secondary. I've heard that bonding two Gig-e cards doesn't realize much of an improvement FWIW, so I assume latency is part of the reason it's slower.
Photos.
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!
so why do FireWire 400 readers still consistently beat out USB 2:
heck, those benchmarks show that even using FireWire 400 to read a PIO CompactFlash card still beats USB 2.0 UDMA reading a UDMA-enabled CompactFlash card.
Comment removed based on user account deletion
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
good point. and to be honest, most people don't need FireWire 800/1600 just to transfer a few documents or spreadsheets--or even photos & mp3s--to their computer. the few seconds saved doesn't justify the added cost of FireWire over USB. nor do they need to use a high-speed data bus for their mouse, keyboard, webcam, printer, scanner, or what have you. so it makes sense that USB is more prevalent than FireWire.
however, FireWire is still extremely useful (and crucial) to certain professionals who regularly work with large files or have to move around large amounts of data, like hi-res/raw images, lossless audio, hi-def video, etc. that's why FireWire is still pretty standard in high-end music & video production equipment. so the idea that FireWire is dead (or can simply be replaced with USB 2.0/3.0) is just poorly informed.
even the military still uses FireWire for things like the the F-35's vehicle systems network:
the IEEE-1394B data bus is similarly employed in the F-22 Raptor for which it was developed. and NASA also uses it to monitor debris during launches amongst other mission-critical applications.