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Seagate Barracuda V Serial ATA Drive Reviewed
Mike Parsons writes "Andrew and Adam over at Explosive Labs have a nice review up on the Seagate Barracuda V, one of the first production Serial ATA drives. Keep in mind, Generation 1 of Serial ATA was not meant to be a 'incredible performance jump.' Rather, its intended purpose was to make the industry transition seamless to allow time to mature the future generations of SATA. Generation 2 and 3 of SATA show more promise for those interested in performance, as white papers behind them gives you the nice fuzzy feeling for speed!"
The problem with parallel data transfer is that, if you have lots of data channels running at the same time, you have to synchronise the arrival of all this data. It's very difficult to do this at high speeds (if you look at your motherboard you'll probably find a few places where the track wiggles back and forth to synchronise the arrival of data).
In recent years, it has become possible to run data connections at very high speeds - but only when you have only one data line. A USB 1.0 connection is comparable in speed to an ECP parallel connection, and there are far faster serial technologies nowadays.
Like car accidents, most hardware problems are due to driver error.
This is one reason why SCSI is so much faster/more expensive; all scsi controllers have this functionality so throughput is maintained even when the parallel data is clashing.
Whilst serial is theoretically slower than parallel, by removing these synching issues you can guarantee better performance in consumer-priced hardware. At the server end, SCSI will remain as price is less important than performance, and as I said, parallel is still more efficient if it has a decent sych algorithm *on board*.
I'm not so much interested in the performance advantages of S-ATA, rather the fact that it finally kills off ribbon cables. It must be the most limiting factor inside any desktop PC. In my tower I have trouble making even long cables reach drives at the top of the case, so they have to be mounted halfway down. In my Shuttle XPC the cables are shorter, but even they have to be 'rounded' and routed around clips to reach the combo drive without taking up all the space inside. Other people complain about the airflow restrictions several ribbon cables cause inside a machine.
In short, I don't care that (Gen-1) S-ATA starts at 150mb transfer instead of 'older' 133mb. I care that it makes building a PC easier, more space inside future barebones machines and PC manufacturers can use more interesting cases than the usual rectangular stuff. I'm excited about the possibilities it offers right now.
insignificant sig
theres another review at storage review
Gyrate Dot Org - "Where high-tech meets low-life"
Anyone know why this was implemented? The article (now /.'ed) doesn't explain the reasoning, just that it exists. Why get rid of the old MOLEX? Since an adapter is included with the drive it doesn't seem that there are any new voltages required. What's the deal?
Is this just another one of those PITA upgrades?
I always thought parallel was faster
:-)
:-)
Yes, provided they both run on the same clock speed. In this particular case they're not.
When you ramp up the clock speed of the parallel bus you get all sorts of problems (synchronisation issues, multiple wires affecting each other's capacitance, inductivity and such). One way of avoiding those problems was UltraATA's 80 wire IDE cable. And that came with increased price tag, and didn't ultimately solve all the problems, it just postponed them for a generation or two.
The other way was to abandon parallel all the way and go serial. Since with serial (one pair of wires) you don't get any above mentioned problems you can ramp up the clock much higher, and thus get better thrhoughput, although you're transfering just one bit at a time.
At first it sounds counter-intuitive, but it just goes to how much intuition is worth.
Oh wait, too early in the morning. Was the USB comment a joke?
If you want a fast parallel protocol, think about trunking multiple gigabit ethernets. Instead of running bits in parallel, you run packets in parallel. You get more bandwidth, without having the timing issues of a bit level parallel cable.
Running multiple serial links in parallel is also a win for fault tolerance. If one cable is sliced, the connection is still up, just slower.
I don't expect to see multiple SATA cables to a single drive, but I wouldn't be surprised by multiple SATA cables to a RAID array.
I couldn't find out nowhere answers to this 2 questions:
;-)
- does ALL SATA adapters + disks supports hotswap?
- does SATA under Linux support hotswap?
And yes, I know www.serialata.org
OK, I'm not a luddite, I understand that progress is a Good Thing (TM) but am I the only one getting dizzy at the speed at which the hard disk drive industry seems to be moving?
In the last five years, typical hard disk drive sizes have increased more than ten-fold, transfer speeds have shot up too and prices have come right down.
The net effect of all these factors is that HDDs have now become commodities and many manufacturers - put off by both the shrinking profit margins available and the high investment costs of developing the next generation of drives - have left the business.
There are now only four major players left, and all of them are doing whatever they can to maintain profitability. Cranking up volume only works so far - there are only so many customers out there, especially in today's economy - so manufacturers have looked to cut costs elsewhere.
Two critical areas that seem to have taken a major hit are quality control and warranties. More and more drives (and in some cases, entire drive families) seem to be failing at every given opportunity. Meanwhile, the length for which they're covered has shrunk back from (typically) three years to the minimum one.
Sure, at the high-end, speed will always be appreciated, but how many of us run render farms?
The market is near-saturated (not everyone needs 200GB or even 20GB, because not everyone is a MP3/MPEG/whatever addict) and that situation isn't going to change any time soon.
I would be much happier with an industry that still has some real competition and offers customers reliable, well-supported products in five years time than one that has breakneck-speed products from top to bottom but which break down every five minutes.
For 99% of users, data integrity is the holy grail and everything else comes a distant second. I wish manufacturers would remember that.
"Accept that some days you are the pigeon, and some days you are the statue." - David Brent, Wernham Hogg
Firewire. IEEE1394.
You can get Firewire hard drives right now. You don't have to wait for them. You can get Firewire enabled motherboards right now, too. Nice round, thin cables. Nice hotpluggable connectors. Faster transfer speeds (Firewire2 will leave SATA in the dust).
The Seagate drives may be a tad slower, but if you want to build a home multimedia server that will sit in your living room, they have the benefit of being unbelievably quiet.
At 24dB, you have to put your ear to a Barracuda drive to hear it, whereas the Western Digital drives put out a whopping 39dB!
If I remember things correctly this is to make it possible to run many different voltages (something like 3) to the drives, suitable for different sized drives.
The spec can be downloaded here (about 1 meg), if someone cares to verify my claims. It's all there.
.: Max Romantschuk
> 15-Pin Power Connector? What's all that about then?
That's what I thought, too, when I first saw the new connectors. It seems we're trading huge data and slim power connectors for slim data and huge power connectors. Why didn't they take this opportunity to move entirely to 5V drives, just like notebook drives, and have a single power connector? Yeah, they'd have to design entirely new drives rather than just slapping on new drive electronics, but it took long enough even as it is, so they might as well have.
And IEEE1394 is just serial SCSI, so why bother with that technology, just buy Ultra-LVD SCSI drives, operators are available right now.
The point is serial ATA is a simple ATA-style replacement. The drives will be cheap because the controllers will be cheap.
Firewire (or SCSI) are not cheap. They are not an equivalent product. Sure, it's BETTER, but it comes at a price some are not willing to pay for an desktop, MP3 server or what have you.
THIS THING CAN TURN ON A DIME, MACROSSZERO STYLE ALSO FUCK BETA, ~NYORON
Alright so far most of the posts are misguided, so I'll answer a few questions. But first, this was mentioned in the slashback that is still on the front page. Please post any corrections.
1a. Yeah!, faster drives.
No. Find me a drive that can use PATA-100 to the max let alone PATA-133 and I'll be a very happy customer. Current drives do not use current capacity, the only time the bus becomes an issue is where you are bursting from the drive cache to the controller, which is not enough to really worry about except in certain situations (The same data is read continuously).
b. Yeah!, Faster drives.
No. Why a second point? The first point dealt with bandwidth. This one is for latency. Please remember that most SATA controllers on motherboards, etc (atm at least) are actually a bridging chip to a PATA controller. This incurs a slight latency delay. If you do a lot of small file accesses you will be effected.
2. Whats the point we already have enough speed?(ie I already know 1.)
a.The point is smaller cabling, making cases less cluttered, meaning better cooling, and easier to keep wiring neat and out of the way. Why no use rounded cables? You didn't think the cables where a ribbon shape for looks did you? The cables are meant to be ribbons to reduce the interference between each pair (limits it to the pair on each side). Rounding the cables causes all pairs to interfere with each other resulting in a much shorter maximum cable length before there are too many interference errors on the bus.
b. Point to point cabling, knock a cable loose, or have a misbehaving drive and you loose one drive. With PATA you can loose 2, or with SCSI you can loose up to 14 (Wide, not typically a problem on modern auto-terminating devices)
c. You can disconnect a drive from a powered controller without risking blowing the controller chip (Possible with PATA). Making removable hard drive cradles finally usefull on ATA systems.
d. Longer in-spec cable lengths. PATA cables (Sorry I forget the length off hand) can't reach the top 5 1/4" drive bay in a full tower case. SATA cables can. Why not use longer PATA cables? Cables longer than PATA spec tend to suffer badly from interference based errors, resulting in a lot of resends on the bus, sometimes causing bad data on drives.
3. The performance isn't what I hoped (or a WD JB is faster)
This drive isn't intended to be the fastest on the block, it is meant to be quiet. Seagate drives have the new fluid bearings, they haven't been the fastest on the block for a while now, what makes you think this one would be different?
I personally think this is a good drive to be first to SATA, as the people likely to appreciate the quiet drive would also desire the better air flow offered by smaller cables, meaning slower case fans, and a quiter PC.
4. Why don't they compare a PATA Barracuda V vs a SATA Barracuda V.
The PATA has a 2mb cache the SATA has an 8mb cache (and a slightly faster access time, by 0.6ms). They aren't directly comparable, the SATA version is obviously aimed to be the top of the line model.
5. The power connecters. The Barracuda V requires the same power voltages that current PATA drives do, so an adapter works fine. However it was intended to supply drives with multiple voltages (such as 3.3v, 5v, etc) so that the electronics can use a different voltage than the drive motors, reducing the power consumption of the electronics, and therefore the heat output. Some drives get very hot, and every little bit helps.
I think thats all.
High speed USB is 480 megaBITS/second
which translates to 60megaBYTES/second
Serial ATA is faster.
--
Find me one disk that can push more than 40-50MB/sec and I'll give you a cookie.
So, Serial ATA would be faster, if the disks were faster.
Karnal
I'm playing with my first two SATA drives, and one thing I find very careless is that the connectors are very easy to knock off the drives. This is not a problem for me as I am designing a RAID box where they slide in, but for a PC, somebody is going to have to add detents or friction locks to these connectors or we are in a world o' hurt. By the way, my IBM SATA drives have the conventional Molex 4 pin power connector for legacy PC applications which you can use instead of the SATA power connector. Seagate was too lazy to put one on their drive, or maybe they need the 3.3V input on the SATA power connector which is not provided for on the Molex connector which is only 5V/12V. Oh, and one other thing, SATA 2.0 phase 2 which will be 300 MB/s won't help at all with performance until and unless the drives go past their present 50 MB/s native transfer rate. Hell, the 150 vs 133 vs 100 agrument of SATA vs PATA is silly when you consider the modest speed requirements of the drives being built today. Raw transfer rate only appears to be increasing 25% per year anyway, so it will be years before we even give a damn about the 150 MB/s "limit".
What are you talking about? USB is slower than SerialATA not faster... Much much slower in fact.
Here's a quick comparison
SerialATA 1.0 - 1.2Gbps (150Mb/sec)
USB 2.0 - 480 Mbps
USB 1.1 - 12 Mbps
Firewire (IEEE1394) - 400 Mbps
Parallel Port - 1 Mbps
Serial Port - 0.115 Mbps
Figures taken from the actual spec on serialata.org and from here.
Nick...