back to article eSATA: A doomed stopgap?

The external SATA (eSATA) interconnect is merely an interim idea and the coming of USB 3.0 will kill it off, according to Verbatim's EMEA business development manager Hans Christoph Kaiser. The background is that eSATA, running at 3Gbit/s (around 300MB/sec), is meant to connect external disk drives to PCs using the SATA protocol …

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E-SATA on high end products only?

I'm currently buying HD external caddies from Ebuyer for about 12 quid each that have ESATA on them.

That said it is true that many machines lack the ports for it.

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eSATA on desktops is cheap

Almost all desktop PCs have spare SATA ports on the motherboard and a bracket with an e-SATA socket and an internal SATA lead is available for very little money. (Aria sells the Darkstar E-Sata Bracket and Cable for £1.44 inc VAT.) Many motherboard manufacturers include such brackets with their motherboards.

As USB3 is not likely to be common for 2 or more years and will NOT be transparent to the OS (unlike e-SATA) and WILL require an additional controller board for all existing PCs, I think that e-SATA will have a brightr future than implied in your article.

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simplistic reasoning

If we follow your logic, we would all be using Firewire800 now, since it leapfrogged USB2 quite some time ago. But it never happened. The reason USB3 will kill eSATA is because USB can be used for much more things than just disks.

That is the (only) reason USB will take over. Although I think eSATA will still stay around because it is so bloody simple, your data/control go directly from SATA controller to harddisk. Unless harddisk manufacturers start producing harddrives with USB3 connectors...

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Paris Hilton

eSATAs been around a while

I have a mobo thats around 2 years old which has eSATA. I also brought a Freeagent ext HD for use with the eSATA port. Only thing I could never find was the cable. I used USB in the end.

So much for progression

Paris, as her external ports are guaranteed have no compatibility issues

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Doesn't USB still suck ?

USB's theoretical speed is well and good but:

1- I've never reached it. Not even close

2- When doing file transfers over USB 2.0, my PC suffers from mini-freezes

3- Some of my USB 2.0 periperals won't work, or will even hang my PC, when connected at 2.0 speeds, I have to force 1.0 to get them to work.

On the other hand, I never had a problem (neither speed nor compatibility nor sluggishness) with FireWire.

My take on it is that early USB was designed for slow periperals: kb, mouse, printer... and specifically not HD. There must be something in the way USB 1.0 and 2.0 were done that made them unreliable ressources hogs for high speeds/big transfers.

Do you know if USB 3.0 fixes that, or is it just a faster release of them same very touchy s**t ?

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Anonymous Coward

Mousing

This is good news for us professional mousers. I can whizz around my multiple monitors so fast I find there isn't enough USB 2 bandwidth for my mouse.

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Anonymous Coward

It's academic until solid state drives are everywhere

When you're copying huge files then burst speed's irrelevant anyway.

When you're read/writing all over the shop the same is true.

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Flame

Addin-cards

Okay so you could possibly need an add-in card to add eSATA to a desktop, more likely though you'd get away with an eSATA to internal SATA bracket at a couple of quid and an eSATA external hard drive case (I went down this route and it cost me about £10 as I already had eSATA on my desktop).

The same arguement could be applied to USB 3 too. I mean existing desktops are going to need additional cards and I bet they're not going to be cheap when the first come out (at least not under a tenner which I can get a USB 2 card for) and if you have a laptop then you've got to spend even more on a USB 3 card (that's assuming there will be a cardbus version released with everything going over to Expresscard).

Sure USB2 is more popular at the moment but I don't see eSATA going anywhere at the moment.

Rob

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Alert

fair enough, but.....

the 3 motherboards I've gone through in the last 4 years all had 2 x eSATA ports (the 2 newer ones had eSATA2) and of course 2 or 4 usb2. True I haven't seen many laptops with eSATA but I have seen some.

One suggests that eSATA is not as dead and non-widespread as the author implies..... but USB will always be bigger, this I agree on.

/me can't wait for 6GBit/s drive transfer speeds :)

now all we have to do is make the drives themselves capable of that kind of sustained speed.

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Anonymous Coward

eSata needs more support

I bought a portable drive enclosure with USB and eSata from Overclockers; coupled with a 7200 rpm 2.5" hard drive it makes a great home for my virtual machines (try copying VM disk files over USB). In the office the drive slides into a slot in my desktop machine (a 3.5" drive bay fitting that came with the enclosure) and the drive works as good as an internal drive. When I'm out on the road the drive slides out and works as a USB drive with my Dell laptop.

As for eSata support, it is bad, but "professional" laptops like the Dell Latitude E6500 have eSata. A big problem is the storage vendors (WD, Seagate etc) aren't supporting eSata, so I had to go an build my own.

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Real world speed?

It is all very well talking of the raw Gbit/sec speeds, but the whole USB standard sucks from a technical point of view, and often firewire disks at 400Mbit/sec would comfortably out-perform USB 2.0 at 480Mbit/sec. What will USB 3 *really* deliver?

The only real attraction of USB 2 external HDD is the small ones can be powered from the USB port (so long as you don't try a long extender cable). Will that still work with the interfaces needed for Gbit/sec USB 3?

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Boffin

You missed a few points

1. The actual 3.0 pinout overlays the normal one so you can use 2.0 devices, so it is not a clean backward compatibility story like 1.1 to 2.0. It is backward compatibility at some extra cost - connectors, silicon, etc. The cost may end up comparable to the cost of an eSATA port.

2. USB2.0 relies on the host CPU for one thing too many and is very CPU intensive.

In any case, you are missing the main advantage of USB over firewire (or eSATA for that matter). It is the hub support. A consumer can easily connect many USB devices and a board designer can easily add ports using relatively low cost electronics. While eSATA in theory can support multiple logical units on the same channel and the firewire spec should have allowed for hub devices, in reality these are nowhere to be seen. So USB coming along had no problems winning the market despite its technical inferiority.

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Alien

What I know is...

...that I have WD 500GB disk which supports eSATA, Firewire and USB...my company laptop does have an eSATA port (DELL E6400) and I bought an Express card for my home laptop.

This easily allows me to use my WB disk as the place to have my virtual machines to run on, (and movies for that matter :) )

I agree that USB3 is the future, but that is just because most users just don't want to have to buy a card and an eSATA disk/encasing and cabling, otherwise they could get proper performance today not next year. BTW USB3 cabling will probably cost as much as eSATAs so it's just the masses being taken driven....bahhh bahhhh

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Dead Vulture

Poor maths

Poor maths there...

4.7Gbit/sec ≠ 470MB/sec

4.7Gbit/sec = 601.6MB/sec

Seriously, it doesn't take much to do (4.7*1024)/8.

On another note, I would say eSATA is more likely to die than FireWire. eSATA is a one trick pony - it does storage only. As good as the transfer rates may be, it's not as convenient as either firewire or USB. Firewire 400 still beats the pants off USB 2 for sustained data transfer, despite having an 'inferior' specification, and it has many uses which USB can't match, most notably digital video (DV) and high end audio (see products like the DigiDesign Pro Tools 003 rack) - but it obviously does much more than eSATA and is well established, so is more likely to survive.

But having said that, if eSATA 3 matches the SATA 3 specification for speed, then I'm sure that purists would much rather have the speed of 768MB/sec (which is probably more guaranteed than any 'burst' speed supplied by the inferior USB 3 specification). This will be especially important for those doing (again) digital video, especially HD, and high end multitrack audio. The other benefit of eSATA is being able to put the external drives into a RAID, which you can't do with USB (or at least, not in the same way, and not without taking a hit to performance).

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Never had a USB HD work reliably

I've had a few USB hard drives - both 2.5" and 3.5" ones, always been a pain, numerous times XP/Vista wanted to format them before it would look at them, even though the drive had been used the day before! Reading from USB drives not so much a problem, but writing to them has always been hit and miss.

Eventually I bought a d2 quadra (has USB2/FW 400/800 and eSata and comes with all the cables) and an eSata express card for the laptop. Has worked *every* time, its quick, and great for video editing. USB3 drives might actually work properly, but until thats proven, its eSata for me for external drives every time.

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Paris Hilton

yeah right

Esata seems like a no-brainer -- a straight-forward extension of the existing internal sata bus, and because of that, obviously pretty fast (and presumably very cheap and easily supported as well). Why _wouldn't_ a manufacturer add it?

USB, on the other hand, while a convenient way to hook up low-speed devices, has a long history of unsubstantiated hype (aka "lies") and crap implementations when it comes to more demanding applications.

I'm sure USB3 will get support, but it seems far to early to assume it's actually usable or good.

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USB vs eSATA vs FW

USB relies on the host CPU (unless there's some fancy accelerator tech I haven't heard about though I am aware not all USB motherboard controllers are created equal), but eSATA is presumably DMA - using the same motherboard controller as the other internal SATA ports and FW has it's own processor.

However, since USB can be used for _everything_ wired to your PC, including your coffee cup warmer, it will be used for everything, because the interface will be extremely cheap. If you want real throughput you probably won't be using USB, but since not everyone needs real throughput, those people will make do with USB.

FW can also be used for more than just HDDs, so it might be cheap, but it might get abandoned in the face of USB 3. That would leave POeSATA to be the storage choice. BUT we're forgetting power over ethernet might be just as appealing.

Then there'll be short range high performance wireless links coupled with wireless induction for power.

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Anonymous Coward

'ang on a tick...

If the new SATA spec is 6Gbps, then the eSATA version will doubtless be identical since eSATA is just SATA piped to a posh socket on the back panel of the PC. And if it's already built into the chipset on the MB, how hard can it be to bung in a couple of lines on the board to connect it to the socket?

Maybe nobody needs the extra 1.3Gbps of SATA over the USB 3? Actually, I wouldn't mind having a bit more throughput since I run other OSes from eSATA externals now, but I'm probably the only person on Earth doing so.

And I guess the USB overheads will mysteriously vanish in USB 3 as well.

Mmm, right-oh.

As you were then.

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A stopgap article

Slow news day? eSata pointless? Well blow me - also it's not as rare as you make out, most mid-range mobo's come equipped with an eSata connection these days never mind high-end and alot of /decent/ notebooks (ie not netbook priced notebooks) have them.

Also the card you linked to won't speed up your transfers as it connects to your PCI bus and is therefore limited by it's 33MB/s connection.

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raw speed versus real performance - long live esata

Raw speed is not what most people really want to know, just the only info easily available info

My experience with USB disc conenction is the performance is usually way below what you would expect, and is also very eratic - just watch the time remaining when copying large files on windows.

Also USB often puts a fairly heavy load on the CPU which slows down everything.

I've found that on many machines, trying to run a Virtual Machine from a USB disc is a non-starter - it will often crash within 5 - 30 minutes

No such problems with eSata connected discs - fast, reliable consistent, and well worth the small inconvenience of the PC card and cable. Oh yes - and for real speed I've found that an express esata card normally knocks spots off a cardbus card

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Bronze badge

Native USB 3.0 drives?

It's possible to imagine that USB 3.0 will be integrated direct into drives. In that case it would be possible to eliminate SATA from future motherboards provided that there is BIOS support for USB 3.0. Of course USB has higher CPU overheads than SATA, but processor power is not in short supply these days.

For the very fastest access, SSD cards directly plugged into PCI-X slots would do the trick, although that, again, needs BIOS support for boot disks. Future PCs with SSD cards for the system and hard disk support via USB 3.0 for bulk data would make a lot of sense. An intelligent operating system could even automatically place data onto the right sort of location based on access patterns.

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Boffin

eSATA at sata3 versus usb3

I disagree, eSATA is becoming more popular. Storage is prevalent in many areas (admittedly less than USB) and eSATA is the native interface - it talks directly with the controller, making it easier to develop for. USB3 is still a long way from being switched on to mass market penetration - eSATA is here and now. IMO USB is for memory sticks, printers, other peripherals and devices. eSATA is for storage because of the direct connection and ease of use for SATA protocols.

When USB3 is up and running, so will SATA3, which is better, faster and with less overheads?

//lamboy

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USB is consumer level

Surely the problem with USB is that there's no guaranteed throughput - all devices compete, and the latency can be quite bad. This is why, for instance, firewire audio cards are much better at recording in real time than USB audio boxes, which have a significant delay.

This doesn't matter so much for bunging a hard drive into your desktop/laptop (so long as you're not doing really high end video work), but it does matter for servers. eSATA is particularly good for expanding either your server or your existing disk array with another large box of disks (and it's a lot cheaper than fibre channel) - I can't imagine USB 3 making many inroads there.

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Gold badge

4.7GBps

Hopefully USB 3 will not require so much CPU intervention as USB2? 480MBps was never achieved in practise and Firewire was much faster.

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The clue is in the name

The other reason USB 3 will be king, is that USB is Universal for all types of devices. Fireware and eSATA have limited device support, almost always high capacity storage devices. The average user just wants one set of ports to plug they low def webcam/ printer/ 1TB external hard disk into.

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Not just speed either...

...but also the fact that people 'know' USB. My Dad couldn't tell you Firewire or eSATA from a SCSI port but show him the back of his PC and he can pick out the USB slot no problem. He's comfortable with the format and unless there is a really convincing argument to change then he (and the majority of the public) aren't going to make the effort needed to make eSATA a mass market sucess. So that leaves business and you've already made a strong case (speed mostly, closely followed by ubiquity) as to why it will remain niche there too.

All in all I think USB 3.0 is pretty much going to be a lock unless they screw it up some how.

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Flame

Some misconceptions:

It seems the article writer has forgotten a few minor problems USB has over firewire (DMA being the most obvious of these), and the USB has compared to eSATA.

USB is a jack-of-all-trades (master of none) that can connect all sorts of devices, block-devices like disks being only one.

eSATA is a pure-bred disk interface, and as such has an interface optimized for this. This allows such things as NCQ, and other native disk commands, that vastly improves performance. Unless the USB3 standard improves the command set as well, not only the bandwidth (and cpu-requirements for handling block devices at those speeds!), eSATA (and firewire) will continue to have the edge for block devices. Period.

But of course some suppliers would welcome the (premature) death of eSATA, since this will make drive speeds seem more equal for external drives. You know, those suppliers that fail to make their own drives look good, MUST make the competition look bad to survive the market.

//Svein

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Bronze badge

Delayed Write Error

Don't get those with eSata, shame if it does die a death

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Boffin

It's not just bandwidth

The big advantage of eSata is that it looks enough like SATA that it is properly supported at BIOS level in all PCs, and will usually work with bootable rescue and backup systems - at full native speeds.

In corporate environments, this means that imaging machines can be done quickly from eSATA drives, and whole-disk backup and restore is quicker and more reliable.

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Boffin

Simplicity is good

Another advantage of E-SATA is that you don't have any sort of USB-to-SATA silicon getting in the way between your O/S and your disk drive, potentially mangling all sorts of things in all sorts of ways. And when it does and you suddenly find you have a Terabyte of junk, "we don't support Linux / Mac / Windows 2000 / you name it". Just Windows 7 (it's 2011), Vista, and maybe XP. (And then there's SMART, and command queueing, and security erase ... disk features frequently not accessible from the USB side of the interface converter chip, unless they raise their game a lot from today's USB2 sub-standards! )

I might change my mind if the disk drive manufacturers ever start building USB3 into their disks (in other words, it gets used for connecting drives internal to a PC case as well as externally, with all ATA features fully usable).

Also Power-over-E-SATA should be a killer advantage: no need to carry around (and lose) yet another power supply brick.

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USB doesn't support SMART

In my experience you won't get any warnings about impending drive failure.

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Anonymous Coward

Killer

USB's always going to be around 'cos it's a general purpose interconnect, and so can be used for hundreds of different things.

Personally I reckon eSATA will kill off Firewire (as the connector of choice for discerning external storage bods), for all but niche video editing stuff.

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Heart

insert title here, ummmm ... TITLE

All I gotta say is thank you for keeping me up to speed with current developments :)

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Anonymous Coward

eSATA/USB combo on 250quid netbook by Toshiba NB100

Bought a 250quid inc vat NB100 from staples last week during their sale. Price now gone up to 294.

This netbook has eSATA/USB combo ports. So market penetration of eSATA is enabled by 1) dual-purpose ports (eSATA and USB) - no extra ports needed, form factor and some costs kept down. 2) Cheap hardware - and netbooks are the fastest selling notebooks.

On the other hand I can see USB 3.0 winning the day as this ought to provide full backward compatibility where as eSATA isn't compatible with USB - unless your USB port is a eSATA/USB combo. It all depends on if USB 3.0 hardware at launch is cheaper than eSATA. eSATA is here now and already has a head start recouping the R&D costs to progress to a commodity item.

I suspect a stalemate of co-existence much like the DVD +/- formats.

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Go

usb will remain king unless they screw up

Firewire - faster...and proprietary...you want to use it...pay our ridiculous licensing fee or else.

USB-1.1 not so fast and not so many supported without special drivers, especially under windoze 98. XP a whole different story....and USB 2.0 eliminated virtually all of that and was fast and easy to connect....

USB...cameras, MP3 players, harddrives...modems...turntables....you name it

eSATA...good idea...up to a point....have never seen much by way of implementation of PCs though...industry has failed to push it enough to make it a "choice" except for the knowledgeable user.

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Pirate

When did Fwire die?

As far as I know its still alive and kicking. Just cos' Apple in their rush to the lowest common denominator can't find a use for it doesn't mean its dead. Just ask anyone who does serious AV or audio - oh noes - are all those AV and audio boys on PCs these days???

Anyone who connects much storage via USB must have a lot of time on their hands and the advent of TB drives will be pushing those USB limits - they can jack the headline figure all they like - people will notice the lack of performance eventually.

USB is OK for keyboards, printers, cameras, phones, opticals (CD and DVD at least) and cup warmers - although its intermittent availability during start up makes a PS2 keyboard a must have with some mobos. Its mass market appeal to lots of common devices and cheap interface will keep it selling.

However, eSata is a serious local storage connection which actually works - its real competition will be developments in NAS because the choice isn't a matter of which Plug n Pray device to use but whether to go local or network.

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Anonymous Coward

eSATA expensive?

I've seen cheap nasty internal card readers with eSATA ports. Simply plug them into a regular SATA port on your motherboard and you're ready to go. Throw in an eSATA hard drive caddy from ebuyer or the like and your choice of drive and you've got an eSATA system for not a lot more than a USB external hard drive.

Of course anyone who thinks that's too complicated isn't going to appreciate the extra 20MB/s* transfer speeds anyway.

*guestimation.

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Can we standardize on an external bus, please?

This entire USB/Firewire/eSATA business has been a big waste of time, IMO.

What I would like to see is more of a hybrid use of the Ethernet port. Put it into true 'network' mode for talking on a net, but have the option to put it into a 'peripheral bus' mode.

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eSata != USB 3.0

There are distinct advantages to eSata vs. USB 3.0. Speed is not the only criteria. Besides the fact that the internal drive cannot sustain either eSata or USB 3.0 data rates, eSata is IMO much better suited for external drives that are continuously (mostly) attached to a system, and especially for external RAID arrays. You can add a nice 4 port eSata RAID controller to a system for under $50 USD these days (25 quid?) that will provide you with a very nicely performing backbone for RAID 5/10 enclosures. So, for a total of under $1000 USD you can put together a 4.5 TB array (6 TB including parity) that takes up about as much space as a shoe box.

I'll admit, I do like USB drives for data that I want to sneaker-net between systems. If it's under 16GB, I'll use a thumb drive. If more, then a nice USB enclosure with a high capacity HD is ideal. Unfortunately, it will be some time before USB 3.0 is as ubiquitous as USB 2.0, so even if one has a USB 3.0 drive, it still be limited to the speed of the system to which it is attached.

That said, I will admit that I will likely be the first person on my block to buy a USB 3.0 drive and controller for my workstation, and possibly a controller for my laptop as well.

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Stop

'Most PCs and laptops don't have eSATa'

I disagree. All of my PCs have eSATA either on the motherboard or available via a supplied PCI backplate (with most of them having it on the mobo) and my laptop has an eSATA port.

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at Anton Ivanov, FireWire does support hubs

I have a 7 port FireWire hub sitting on my desktop right now. And I have several hard drives and DVD burners plugged into it as well as a video capture device and a camcorder.

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eSATA == SATA, just another connector

From reading the comments, I see that there is a fact some people are missing: eSATA is identical to SATA, the only difference is the shape (and quality) of the connector. A SATA connector is rated for about 40 reliable plug/unplug cycles, eSATA several thousands. You can also buy (cheap) SATA to eSATA cables, brackets,...

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Anonymous Coward

USB 2.0 and Firewire are limited to 2TB ...

One issue that hasn't been covered explicitly here is that USB 2.0 and Firewire are both limited to 2TB (32-bit block numbers x 512-byte blocks == 2^32 x 2^9 == 2^41 == 2 x 2^40 == 2TB). Meanwhile eSata supports 128PB (48-bit block numbers x 512-byte blocks == 2^57 == 2^7 x 2^50 == 128PB). What is the size of logical block numbers for USB 3.0? I haven't found that information in a few minutes of google'ing.

In any case, the absolute size of disks that can be addressed is going to become more and more important as giant video files become popular.

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Speed hype vs real speed

One thing nobody has pointed out yet is that USB is a shared bus. Actually, one other commenter did point it out, but they pointed it out as an advantage. It's not. A shared bus is a disadvantage when you're talking about storage devices. With my USB2 connection, I have an approximate bandwidth of 48MB/sec. That 48MB/sec is shared between my external hard drive, external DVD rewriter, UPS, mouse, keyboard, and audio device (Zoltrix 5.1-channel). It may not sound like much, but trust me, it is. Without music playing, I can burn an ISO to CD at an average speed of 48x. With music playing, burning that same ISO reaches a maximum of 42x.

Will that really make a big difference? It depends on what you're trying to do. If you hook up multiple external hard drives, then USB will most definitely slow down transfers when both drives are transferring simultaneously. With an eSATA connection for each drive, each drive would have its own channel, thus its own dedicated bandwidth, so it wouldn't be slowed down.

Also, as others have mentioned, USB is *VERY* CPU-intensive. When playing music from WinAmp through my laptop's internal Conexant HD Audio output, my average CPU usage is 1% (as you would expect when it's not doing anything else). When I switch the output to the Zoltrix 5.1-channel USB audio output, the CPU usage averages 14% (it averages 14% whether I set it for 5.1 or 2.0 channel mode). When I look at the processes, the System Idle Process averages 97% and the System process averages 3%, yet the total CPU Usage shown at the bottom of Task Manager shows 14%. That very clearly illustrates that the USB bus (specifically, sending the audio data to the Zoltrix) is taking up a lot of the CPU's time.

USB is a good idea for general connectivity, though something does need to be done about the CPU usage. But no matter how you look at it, USB is not the bus to use for storage.

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@The clue is in the name

"The average user just wants one set of ports to plug they low def webcam/ printer/ 1TB external hard disk into"

You seriously want to move 1TB of data through USB?

I've just spent almost 2 hours trying to transfer 57GB - and it failed - twice.

Why is it impossible (in the UK at least) to buy a SATA drive enclosure with FW ports?

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This article is flame bait

Honestly, this is an idiotic article. It's not about the theoretical throughput of the bus.

eSATA supports Advanced Host Controller Interface (AHCI), Native Command Queueing (reordering requests to minimize latency), is much less CPU intensive, support RAID, and don't have to compete with other devices on the same (often underpowered) bus.

Firewire is DRM-friendly (I think it has HDCP support?) It's not going away.

USB is great for thumb drives, mice, and For Dummies(tm) who don't know any better than to plug a hard drive into it.

On an aside, OKGear enclosures for 2.5" and 3.5" drives sell for ~$25, and have a switch for eSATA and USB. Silicon Image has a cheap ExpressCard 2-port eSATA adaptor, with Windows and Linux drivers. They work great.

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This again?

Firewire has, yet does not need hubs, since you can chain devices together like with SCSI. Most devices have 2 ports, and you can just keep plugging them into eachother, up to 127 or something. And it's rather decent about sharing bandwidth and keeping latency low.

I don't know who in their right mind would do a 4 disk external raid. If you have data important enough for redundancy, then spend a couple extra bucks and get a case with extra internal drive bays. Or get a hotswap deal to stick into your 5.25" bays.

With reasonable software raid (Those $50 raid cards do software raid too, don't be fooled,) you can raid anything you want. I'm referring to md in Linux and whatever OSX uses. I've not used OSX's version much, but software raid in Linux has most of the features of a high end hardware raid card (online capacity expansion, background rebuilding / consistancy checking, shared hot spare, etc) and it's faster than a couple of the low end hardware raid cards that I've tried. And you could make a raid out of a network disk (AoE), a sata disk, a usb disk, and a firewire disk, and a disk image file. It'd probably be slow as balls since that USB disk would probably run slower than a network disk using 100mbit ethernet, and it'd introduce all kinds of rampant latency, but you get the idea. I've also heard of someone using OSX to raid together 8 usb floppy drives. It's not a good idea, but it illustrates the flexability of the system.

Yes, USB sucks, especially the Intel and VIA controllers, since they do even less of the work than a regular controller, leaving more up to the cpu to deal with.

As to the math, not every single bit in the GBit rating is actually used for data, they typically do some sort of 8 in 10 encoding to get some error checking and data resilliency, so you actually just divide the rated speed by 10 to get the actual speed in bytes.

Don't get me wrong, I've used external USB drives, but I typically do it when I'm not even kind of in a hurry, mostly when backing up users' machines before I reformat or whatever. Then again it was hard to tell whether the shitty computer, shitty drive, shitty enclosure, or USB that slowed things down.

I mostly hope that there's always some alternative to USB that isn't too expensive, since I may need an external drive in the future, and I don't really want it plugged into my mouse port.

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Flame

USB hype, for lowest common denominator.

USB maybe convenient, and cheap (and nasty), but anything which relies on interrupts, and polling, and high CPU use, is pathetic for storage, and other bulk data transfer applications, like video.

eSATA, and Firewire, are far superior for bulk data transfer applications, like storage and media devices, because they can use DMA, unfortunately the USB hype conned people into accepting crippled peripherals.

eSATA was let down by, the moronic lack of power on the eSATA connector, poor "hot-plug" eSATA motherboard support, and poor peripheral support e.g. Seagates' faulty external drives.

Firewire was let down by motherboards, and audio cards, still providing the slow 'a' version of Firewire, instead of the much faster 'b' version of Firewire, a different connector for Firewire "B", and few peripherals supporting the 'b' version of Firewire, WTF were the designers thinking!

I note that Ethernet USB bridge hubs have now appeared, to get around the stupid cable length, and peripheral sharing limitations, of USB. I note that power over Ethernet already exists, so power should not be an issue. I see you can now get all sorts of bridge devices for CAT5 and CAT6 cable, including audio, analogue video, HDMI, etc., maybe this proven cable could be used for other serial data.

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Thumb Up

Marketing at its finest!

Wow --- Let's come up with a new version of USB and tell folks that our large cheap drives are just as good or better than the alternatives because the signaling rate on the connection to those disks is "USB 3". With any luck, by the time they've gone out and bought the hardware to do USB 3 it will be to late to return the drive.

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IT Angle

Overhead

Isn't the attraction of Firewire over USB the reduced overhead on system resources? 4-odd Gbps is great but not if everything else runs like a snail on Valium. Doesn't e-SATA have a reduced overhead too in comparison to USB-2? Would like to see some real world figures on comparative resource use.

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