Slashdot Mirror
Asus Delivers Speed Boost With USB Attached SCSI Protocol
MojoKid writes "When USB debuted in 1999, it offered maximum throughput of 12Mb/s. Today, USB 3.0 offers 4.8Gb/s. Interestingly, modern USB 3 controllers use the same Bulk-Only Transport (BOT) protocol that first debuted in 1999. Before the advent of USB 3, relying on BOT made sense. Since hard drives were significantly faster than the USB 2 bus itself, the HDD was always going to be waiting on the host controller. USB 3 changed that. With 4.8Gbits/s of throughput (600MB/s), only the highest-end hardware is capable of saturating the bus. That's exposed some of BOT's weaknesses. UASP, or the USB Attached SCSI Protocol, is designed to fix these limitations, and bring USB 3 fully into the 21st century. It does this by implementing queue functions, reducing command latency, and allowing the device to transfer commands and data independently from each other. Asus is the first manufacturer to have implemented UASP in current generation motherboards and the benchmarks show transfer speeds can be improved significantly."
like I like my women, FAST, WIDE and SCSI
When USB debuted in 1999, it offered maximum throughput of 12Mb/s.
Well, no, it didn't. It was based on 12Mb/s signaling rate, but delivered substantially lower actual throughput. There's a paper on the usb.org website that runs through it all, showing how the relatively large overhead of the protocol affects throughput.
It isn't proprietary - it is part of the USB3 spec, but hardware that actually supports it appears to have been missing, until now. There has been a Linux driver for a while now, and TFA says Windows 8 will implement it too.
With UASP sufficient to provide a good disk interface, will new motherboards keep it simple and eliminate the SATA controller and ports? Will new internal hard drives simply have USB connectors?
According to Electronic Design,
So, a kernel could have a single SAS driver that supports all SAS, SATA, and USB block devices. This could be a marvelous convergence.
USB debuted in 1999?
I had USB in Windows 98.
TFS is just plain wrong. From https://en.wikipedia.org/wiki/USB...
"The original USB 1.0 specification, which was introduced in January 1996, defined data transfer rates of 1.5 Mbit/s "Low Speed" and 12 Mbit/s "Full Speed". The first widely used version of USB was 1.1, which was released in September 1998. The 12 Mbit/s data rate was intended for higher-speed devices such as disk drives, and the lower 1.5 Mbit/s rate for low data rate devices such as joysticks."
Do what thou wilt shall be the whole of the Law
This finally resolves the biggest problem for USB interfaces and hard drives for audio. The primary factor for performance in audio has always been access speed (seek time), and not throughput. Audio software has to access dozens of separate audio files in a very timely manner frequently, and the overhead of the USB protocol has always been a wrench in the gears. From what I'm reading, UASP offers the same advantages NCQ (Native Command Queuing) offers in SATA, which allowed for much higher track counts on the same drive rather than spreading files across several drives, which was a pain in the butt. It was only with NCQ in ~2005 that SATA finally caught up with SCSI-2 (ca 1994) in audio performance, provided the drive was 7200rpm or faster. Firewire has some form of queuing system built into the host, so it's always been better than USB for audio, but it is vanishing from laptops and desktop motherboards, even Apple products.
Now watch how long it takes before audio hardware manufacturers adopt it, and feel our pain. The first Firewire audio interfaces came out about 4 years after Firewire was standard on Mac desktops...
War as we knew it was obsolete
Nothing could beat complete denial
- Emily Haines
Just when I'm really, really tired of the acronyms, there's SCSI over USB. What's next, orange juice out of apples? Kia to Tesla conversion kits? Vegan outback steakhouses? Elegant Perl code?!
esata is just sata with some very very minor phys layer changes. its still sata.
and sata is identical to sas at the phy layer (controllers often can be used for both with diff firmware). ide, as we once knew it, morphed into sata and sata and scsi are now 'friends' in a way.
ahci is the 'real' form of sata. old compatible stuff was just that, running ide over over the sata phy layer.
trim exists whether you run esata or local sata. trim does need ahci (ie, true modern sata) but does not care or know if its internal or external.
just to clear that up a little..
--
"It is now safe to switch off your computer."
search for 'vertical usb flash' and you can find internal tiny usb 'thumbdrives' that mount right on the 10pin (iirc) usb mobo header. inside the case. has been that way since about the start of vista days (1gb was somewhat common as a 'cache' you could use).
--
"It is now safe to switch off your computer."
You can only use six non-modifier keys at the same time. This is a problem for playing older multiplayer games. See appendix B.1 of the USB HID 1.1 specification.