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Latest SCSI Drive Reviewed
Sivar writes "StorageReview got their hands
on a Maxtor Atlas 10K V, the first SCSI hard drive in more than two years to double
capacity. Considering how quickly storage was improving just a few years ago, and other news like Intel's cancellation of the 4GHz Pentium IV despite AMD's lead you have to wonder if the traditional predictions of the end of Moore's Observation are actually beginning to come true."
The other two models are 73 and 147 according to the article.
What the fuck do hard drive capacities have to do with "Moore's Observation," which was about transistors?
[
It's a doubling of the density of transistors every 18 months. It doesn't say anything about magnetic storage density or the clock speed of chips. Intel cancelling the 4GHz P4 was just admitting (and it's about time) that cranking up the clock speed is not the best way to improve CPU performance. There is no indication that will prevent Moore's Law from continuing
Jason
ProfQuotes
Unfortunately Moore's observation has nothing to do with clock speed or hard drive capacity. Plus one, and minus two?
i wont be moving back to IDE.
First, Moore's Law has nothing to do with hard drive storage space. That said, hard drive capacities have been growing at a pace exceeding Moore's Law for several years now. If that rate slows down, it'll probably still be a pretty fast pace. Besides, these are fast SCSI hard drives. You have to look at IDE hard drives to really see storage space improvements.
Second, Intel cancelled their 4GHz CPU because of heat problems. It turns out that Intel's engineers just can't get the leakage current down to low enough levels. But again, Moore's law has nothing to do with clock speed... the metric is the number of transistors on the chip. In this regard, Moore's law is still on track. To counter the heat issue, logic designers will have to rethink their designs to do more work per clock cycle. AMD already does this with their chips. Intel is going down this route too with its Pentium M. Same with IBM's G5. The Pentium 4 is a horrendous example because Intel designed it to be inefficient so they could ramp its clock speed. Well now the consequences of that stupidity is showing.
You know, I've heard that the human brain operates at about a 10Hz frequency, has 100Bln neurons, and trillions of interconnections. Amazingly, its power dissipation is at around 40W. (And its MIPS rating is on the order of 10^15 instructions per second). Clearly mother nature got it right for efficient computation.
mean time between failure (MTBF)...
SCSI 1.2 million hours
SATA 0.6 million hours
That and SATA is still NO WHERE near the performance of higher end let alone mid-range SCSI drives.
Serial ATA will not be able to compete with SCSI in the server market until implementations of native command queueing are complete. Are far as I know, none of the current SATA drives on the market currently support NCQ.
SATA:
SCSI:
And yes, you can tell the difference, even as a "normal" user.
This doesn't mean SATA sucks. In fact, it's quite good for the target application: Low- to medium performance workstations. And it also doesn't suffer from bus termination-fu and other black arts of SCSI configuration. But there are still clear benefits to SCSI.
Schwab
Editor, A1-AAA AmeriCaptions
yes, I have OLD SCSI U160 drives and tried the new fast SATA drives for my Media array.
the old SCSI drives from 4 years ago kick the ever living crap out of the SATA drives.
this is non raid performance. When capturing RAW video from a TARGA 3000 card (A $7,500.00 professional video capture card) the SATA drives would drop frames and completely CHOKE after 5 minutes of capture at 40Megabytes per second.
the old SCSI drives with an even older 29160 scsi card had zero problems.
I hope that SATA will speed up eventually, but SCSI is drastically faster, even from ages ago.
I'm betting that SCSI U320 makes the fastest SATA stuff look like a complete joke.
Do not look at laser with remaining good eye.
I recently replaces an SATA array on a database server with SCSI disks. I had used WD Raptor disks which, from the specs, seem like a nice drive. But when I got the SCSI array put together, it was embarrassingly fast. There's something about SATA (and ATA) that makes it suck at synchronous, random loads.
I see 45-50MiB/s from my single 10k Raptor SATA. I know it's not SCSI, but I figure for open comparison. At work in a Dell 670 workstation with a RAID0 of Seagate 10k's I see around 120MiB/s. Not too shabby considering the parts involved.
wdd
First of all, Moore said nothing about storage, only transistors in semiconductors.
If we assume there is a similar correlation with density on magnetic media, it still doesn't necessarily mean it's slowing down now.
AFAIK, drives had a major slowdown in the past around the 8GB mark and then suddenly 20GB->120GB appeared very rapidly, and then slowed down a bit then. I'd need to do alot of research and get some actual data before making a statement about exponential growth of magnetic storage density and whether or not it is feasible to continue or at what rate in the future.
Also, narrowing the comparison to just SCSI devices is foolish, as they are rapidly being supplanted by cheaper ATA based devices. Yes SCSI is superior, it always has been. Except in one place, cost per unit storage. And as they say, quantity has a quality all its own.
Also, lower costs disks such as SATA enable alternate means of increasing capacity and performance such as low cost RAID. SCSI used the RAID argument over mainframe SLED solutions to win in the market. Now mainstream SATA drives are using the exact same argument vs SCSI. The same principles that were true in the 80s and 90s are true now: more disks have inherant advantages, and can be flexibly arranged to provide whichever one you want whether it's performance, capacity, or reliability, in varying degrees. All for lower cost even with the added hardware overhead of the controller.
Finally, there's one more factor that can be causing the slowdown in disk expansion. The fact that file sizes do not expand at the same rate, so demand for larger storage is being outpaced by the increase in density. I'd be interested in seeing what the average webpage size is from 1994-2004. I'm sure it goes up really quick as features like image support and frames first come in, but then mostly levels off. Word processor documents, even bloated by modern office suites, are still not more than an order of magnitude larger than they were 20 years ago. People still put their school papers and resumes on (GASP!) floppy disks. And their rate of density increase has been zero for quite some time, discounting alternate formats such as zip and usb flash.
As storage continues to increase, we're seeing people actually have enough storage. I remember having to pick which games I could install on my 286 and 486. Now I just throw them on and by the time my disk fills in a year I just buy more disk as it's that cheap. My 105MB hardcard for my 286 cost ~$700 in 1989 or so. The 1.7GB fast SCSI-2 Micropolis HD I upgraded my 486 with the 525MB SCSI-2 Conner cost $900 in 1994. These days I could go grab a 200GB disk for $99 on sale. But the point isn't that the technology is better. In 1994 the biggest disk I could get was about 9GB and cost thousands. These days if I want the bigest thing on the block it's 400GB and costs under $400. What the average user gets in a new machine is much closer to the most advanced part in the market than it was 15 years ago when we had 340GB HDs in home machines and 4GB HDs in highend servers. Where did the highend disks go? RAID replaced them. These days if you want an order of magnitude more than what a major OEM ships as standard (Say, 160GB*10) you go for a RAID, either SCSI or ATA.
Once you're paying for RAID hardware you're getting performance levels in the enabling hardware that make SCSI irrelevant. SCSI has a 320MB/sec bus, command queueing on drives, and a dedicated CPU and cache on the host controller. A highend SATA RAID like 3Ware has 150MB/sec per drive non-shared switched bandwidth, command queuing on drives, and a dedicated CPU and cache on the host controller. Only the 3Ware setup will give you VASTLY more bang for the buck because you can buy more and larger disks to give whatever performance/capacity/reliability you want. A 12 drive SATA RAID10 is going to utterly destroy a 5 drive SCSI RAID5 in every possible way except for thermal output and physical space, which can be
Introducing the new Occam Fusion! Now with sqrt(-1) fewer blades!
Maxtor...
After losing a total of twelve DiamondMax drives to hardware failure, never again. Eight I had purchased, the other four were replacements for four failures.
I had four in two separate mirror configurations fail within minutes of each other. The original eight were bad within twelve weeks of purchase.
My local retailer honored the replacement warranties with more DiamondMax drives. I accepted on the first four failures and those died within 6 months.
Never, EVER again will I buy anything from Maxtor.
There's so little difference between politics and jihad lately...
1. 150MB/s is waaay more than a single drive can push, so it is more than sufficient.SATA is a point-to-point connection, one drive per channel. SCSI may be 320MB/s and support up to 15 devices, but that bandwidth is *shared* among all of them. By the time we have HDs that can actually deliver 150MB/s transfer rate, faster SATA will be available.
2. Maximum number of devices: that's a number you pulled out of your ass. You can have as many SATA devices as SATA ports. 3ware makes nice 12-port RAID controllers.
3. Spindle speed & seek time are the properties of the *hard drive*, not the *interface* (Do you understand the difference?). A SCSI and SATA HD with otherwise identical specs will have the same performance. Also, there are 10000RPM SATA HDs -- the WD Raptors, though they are not very cost-effective. If reasonably-priced 10K and 15K RPM SATA drives are released, they will totally kill SCSI market (which is, I suspect, the main reason they are not available).
___
If you think big enough, you'll never have to do it.
There is a reason high end servers use SCSI drives and not IDE arrays. MTBF being one, sustained transfer rate being another. Your analogy is flawed, because a SCSI array truely is superior to an ATA/SATA array.
Hey whatever works for you.
Blar.
In fact, it's the only computer that's calculated Pi to any decimal place. It offloaded the dirty work to a mechanical devices that it designed and built.
Computers are useless. They can only give you answers.
-- Pablo Picasso
... I can guarantee you most DB guys I know would shit their pants in joy if they could get 15k RPM 9GB drives in bulk. I know of DBAs that buy 18g drives and only use half of them. In theory you only use the inner cylinders, but internal geometry these days is largely divorced from logical geometry.. DBAs who deal with random small writes want lots and lots of spindles striping using lots and lots of hardware RAID adapters.
The super exciting thing about the 2.5" drives IMHO for SCSI is the possibility of boosting rotational speed thanks to reduced media weight. If you could get 1" 20-40kRPM 9GB SCSI or SAS drives and join together 100 of them that would be unbelievable.
Had nothing to do with hard drives, or even processor speed. It merely stated that technology was advancing such that the number of transistors on a chip doubled every 18 months.
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