I use all my USB ports!

I have 6 usb ports on an old pc that is dog slow!

I plug each usb up with a usb 2.0 thumb drive.

I put a swap file onto each one with min/max size of 512 megabytes.

Reboot.

now the 500Mhz pc acts just as fast as a 1.4Ghz pc :-)

It's the spindle, stupid.

Rotational drives - especially consumer level - rarely get beyond 130MB/sec as a peak transfer rate. You then have to factor in the SATA-->USB bridge chip, and also the stated problems of USB having to potentially schedule for up to 127 devices, etc.

Now, if someone could pull apart one of these devices and throw an Intel X25, or other performance SSD [most SATA-->USB bridges will work with any SATA device] then you might get an idea of where the *real* bottleneck starts coming in.

As for multi-disk USB drives - I'd suspect most of these will end up having a Gigabit NIC on them too, seeing as the cost of prepping RAID-capable SATA-->USB bridges will soak up most of the overhead - once you get to that sort of price point, you might as well start looking at adding a NIC, letting an ARM SOC with a slim linux distro do all the RAID/LAN/WebUI work.

It concerns me that people don't seem to realise that the limitation with a multiple gigabit link on USB hard drives is the disk though - especially as most HDDs can't even saturate SATA II at the moment, never mind SATA III.

Steven R

127 Mbps?

Hell after being stuck with around 18Mbps for USB2 for so long I'd have settled for 36Mbps to be honest.

127 Mbps will be a nice boost, I can live with that.

What does annoy me (and I never take stock in it) are these ludicrous theoretical maximums the labs come up with. I usually dived by 5 and that sets my maximum expectations.

Apples and oranges

Why are you comparing observed maxima for USB 3 with theoretical maxima for USB 2? In fact why does this read more like an advert (or maybe an apology) for Buffalo than an article about USB speeds?

...+ a quad core required

The thing thats forgotten is how shat USB is when it comes to computer resources (specifically CPU).

It is one of the worst inventions for anything beyond keyboards/mice.

It sucks the life out of your PC ... why would you use it for high value I/O ? Use a real I/O controller and you can continue using your PC in the meantime!!!!

120Mbyte/s device fails to saturate 400Mbyte/s interconnect

... shocker!

PCI/PCI-E bridge limits too?

This is just a thought, I haven't done the maths, but wouldn't some of the slowdowns come too from the controller connection to the rest of the system, i.e. PCI or PCI Express x 1?

If you have a brand new motherboard come out with USB3 on board, that too will be connected to the rest of the system via a PCI bus and suffer from all sorts of bus contention issues, lets face it there's a lot of inherent traffic moving around your typical PC all the time enough to eat into the benchmarks.

I agree though that the slowdowns are most likely from the limitations inherent in those olde spinny platter devices.

How about everybody stop bitching about USB3 until those chunky MLC SSDs start appearing with dedicated USB3 front ends? (So many TLAs)

Ithankyou.

Faster than eSATA?

127MB/sec?? I have an eSATA RAID attached to my machine here which exceeds 300MB/sec on a single eSATA PM link. I don't think Buffalo know what they're talking about.

USB3 sound like a load of garbage to me - all the overhead of Firewire without the advantages, and barely faster than FW800 at the moment either.

AC @14:35 GMT

You are absolutely right; USB's spec ties performance to the CPU and system, thus making it depend on a lot of things other than itself. I'll stick with Firewire, where applicable.

Hardly suprising

aren't Buffalo the Amstrad of the external drive world. I got a Buffalo Giganet NAS which at best performs like any good 10/100 NAS.

Buffalo specs are unrelaible. They probably just got a USB2 device and put a USB sticker on it.

Could it be the OS?

The Windows driver model is known to be atrocious, and there are vendors offering replacements for USB 3.0.

As far as I could see on both of the quoted articles, the tests were probably run under Windows.

The Reg should try a comparison between Windows and Linux, given the same hardware - after all, Intel did the initial development of USB3 under Linux.

Not an intelligent article

What a stupid article, whinging that a SATA-II hard drive at 7200 rpm doesn't fully use the USB3 bandwidth. What's so shocking about that? If you put a Ford Fiesta on the Silverstone racetrack would you be shocked that it doesn't hit 200mph on the straights?

There is no way of saturating USB3 with a current domestic hard drive. Even a pair of 15,000 rpm SAS drives in RAID0 couldn't fill that much bandwidth. But if you have several USB3 hard drives attached then you would benefit from USB3 if they're all copying files simultaneously. Remember, USB3 is to satisfy computing for the next 6 years, so we won't see affordable devices capable of saturating it for a couple more years.

@ Could it be the OS?

How is it every article has to get back to Linux? Every flipping article you read has some loser say something about Linux! An article about USB 3 and we have some simpleton wanting to compare USB3 speeds on Windows and Linux.... listen no-one cares you understand? No-one cares about how it might perform on Linux. I hate the very mention of the word Linux at this point. Actually, most USB3 devices won't even support Linux, so I would not worry too much about it. In fact I'd be willing to bet Windows would outperform Linux, simply cos the devices will actually work on Windows without you having to hack for thirty minutes in the console to try and make the device mount.

Please get me an icon where people can show their contempt for that useless, 0.05% market share grabbing, dog that is Linux.

Garde Ta Foy

Our dark alien overlords will release the better version, next Christmas perhaps .. if we are good

USB sucks

I'm using it at this very moment for what is, I grant you, a rather unusual project.

Scenario. I have a PC with a CF->IDE "drive" and no optical drive. Normally, I would simply boot and install ubuntu off a USB key but for some reason this mobo refuses to boot Ubuntu in said manner. It is apparantly a BIOS problem (according to some googling)

I want to install ubuntu to an 8GB flash card in that server.

Anyway, my workaround is to stick the CF card into a USB card reader, fire up vmware workstation, build a VM with "Use a physical drive" instead of a virt disk and point that at the CF card.

The process ultimately works fine. I can install the OS to the card, remove it and then boot it in the IDE CF drive bay all without problem.

However, during the installation process using vmware, the PC becomes unusable. It locks hard (including mouse pointer) for minutes at a time. The first time it happened I almost did a hard reset thinking it had hung completely. Eventually it came good in spits and stutters but I had to walk away for over an hour until it was finished. An install which normally takes about 25 mins took 4 times as long and the host PC was unusable during the process.

I've done similar installs using this method in the past using non usb drives without this problem. The problem is the USB interface. It is too CPU dependant. This makes USB cheap to produce but does not make it good.

completely pointless

In the real world of cheap flash memory etc etc people don't even utilise USB 2.0's full potentional so I really don't see the point

Needs an SSD to evaluate USB 3.0 speed.

Or, to at least come close to it.

This article is misleading... from the sounds of it there's nothing wrong with usb 3.0 or the controller and it's clearly the disk that can't physically output more than 130 MB/s.

Calling USB 3.0 slow because the disk it's connected to can't fill up the pipe is a bit like saying my 20 Mb internet is slow because I just visited a site where the server hosting it couldn't output more than 26 kb/s. Completely the wrong end of the stick.

127 devices on a USB controller??

Erm, who's barmy idea was this? Even on my old HP effort (a P200 job) wich only had 2 ports on it, I only managed to connect 3 devices via a powered hub and only then I had only low bandwidth stuff connected to it. It worked fine with a bit of creative use. Of course if you have a massive desk and an unlimited amount of money and time you could daisy chain stuff, but it would be so slow it would be unworkable. It's a bit like public transport: you can't get on the bus if it's full.