Ads
Ads
All about Internal Storage
 Latest Internal Storage articles
Laptop Storage: 640GB And 500GB Drives From WD And Fujitsu

Laptop Storage: 640GB And 500GB Drives From WD And Fujitsu
We're looking at two new notebook hard drives today: Fujitsu’s 500GB 2.5" disk and WD’s brand new 640GB 2.5" model (the largest notebook drive you can buy). The capacities on both products are outstanding, but neither drive is completely perfect. Read More

All Internal Storage articles

Newsletters


  • Ask your question about IT issues
  • Post

Partners

The Games selection

violent : Interactive Buddy Unwind on your interactive buddy: Do anything you want to him, it will earn you money, and you can buy other stuff to torture him with.
crazy : PC Breakdown What is worst than a Fatal Error occuring during a game you did not save? Unleash your rage at your PC in this game. Blow it to pieces, it feels so...
Ads

Sponsored links

Samsung Cramps 24-SSD RAID Experiment

Next news
11:21 AM - March 10, 2009 by David Murphy

By now, the Internet has been abuzz with a new marketing video from Samsung. In it, a group of intrepid--well--Samsung marketers take the company's new 256 GB solid-state drive and hook it up to 23 of its closest friends.

That's right. It created a 24-drive RAID array of SSDs and used it to accomplish a number of simple tasks.  We're not sure what RAID level the Samsung folks are using--we're going to assume RAID 0, since the video seems geared to show off the performance of what a ton of solid-state drives can collectively do.

Or does it?

For some reason, the marketers also don't mention the RAID controller they're using to attach the drives to their system. We can only surmise, based on a pithy search of some of the industry's bigger RAID controller companies, that they're using a PCI Express x8-based controller.  We weren't able to find any quasi-consumer, >24-port SATA controllers running on anything faster than a PCI Express x8 link. Why is this important? Because as cool as the notion of 24 drives in a RAID array might be, it's completely frivolous from a technological perspective.

Just looking at the tale of the tape, Samsung boasts 220 MB/sec. sequential reads for its 256 GB SSDs. Actual performance specs usually differ from what a manufacturer provides, but in this case, just assume that this is the theoretical maximum output of these SSDs. Twenty-four of these drives in a giant RAID-0 array could, in theory, produce a maximum sequential read speed of 5,280 MB/sec. This will obviously be different in a real-world setting, as adding drives to a RAID 0 array doesn't automatically double the data bandwidth.  But push those thoughts aside for now and just cement that number in the back of your mind for a moment. 

Now consider just how much bandwidth a PCI Express x8 connector can tolerate.  Each of the eight lanes in the connector produce a bidirectional 250 MB/sec. transfer rate.  Since the Samsung crew is just reading from the drives for its benchmarks, that leaves a total bandwidth maximum of 2,000 MB/sec.--nearly three gigabytes-per-second smaller than the theoretical maximum output of a 24-drive SSD RAID array.  And what happens when the Samsung group measures the performance of the onslaught of drives? They find a sequential transfer speed of 2,019 MB/sec.

What was that PCI Express x8 maximum bandwidth again? You guessed it. Right around 2,000 MB/sec.

We're not discounting the "cool factor" that come with using a large chunk of solid-state drives in a single array.  Or, for that matter, grabbing said array and jumping up and down on a trampoline while your computer's running.  But it does look a little misleading to use so many of these drives (at roughly $900 a pop) to deliver this kind of performance when a similar metric could have been achieved with, say, one-half the number of drives.  We're only surmising this last point, as it's unclear how much of a performance benefit each new SSD brings to a RAID-0 array.

Still, it's an important lesson to remember for aspiring performance enthusiasts.  Maxing out your storage bandwidth can win you the love and admiration of YouTube geeks worldwide, but know that all the parts of your machine--the tubes, if you will--have to be the correct size to avoid the kind of bottlenecking that the Samsung crew sees on their 24-SSD experiment.  We can only imagine the kind of results Samsung might have been able to show off were it running a PCI Express 16x RAID controller (or, for that matter, a PCI Express 2.0 8x RAID controller).

Do you have SSDs installed on your system? If so, what brand and how many do you have installed? Was it worth the purchase?

Update: Props to Tom's Hardware user Spazoid who's noted that Samsung's full RAID configuration details appear in a quick series of frames at the tail end of the video.  Here's the setup: Samsung slaps ten SSDs onto an Areca 1680ix-24 RAID card, eight SSDs onto an Adaptec 5 Series RAID card, and the final six SSDs directly into the motherboard SATA connectors itself.  It ran two RAID0 arrays build from the drives connected to each controller, with the remaining drives operating in a standalone mode. And the 2,000 MB/sec number?  That's a cumulative total of the connected drives' performances, not a reflection of a single array's performance.

Source : Tom's Hardware US

Talkback
Add your comment
LATTEH 03/10/2009 5:50 PM
Hide
-2+

the way the picture looks it looks like a mother pig or dog feeding her pups LOL

PhoenixBR 03/10/2009 5:55 PM
Hide
-0+

We only need 2 Microns SSD to get equal performance and 3 to surpass it.

"TG Daily - 26/11/2008
Chicago (IL) – Chip manufacturer has demonstrated what is, at least to our knowledge, the fastest solid state disk drive (SSD) demonstrated so far. A demo unit shown in a blurry YouTube video was hitting data transfer rates of 800 MB/s and can expand to apparently about 1 GB/s. The IO performance is about twice of the best performance we have seen to date."

Aragorn 03/10/2009 6:44 PM
Hide
-0+

Where can you buy that micron drive?

spazoid 03/10/2009 6:48 PM
Hide
-3+

All the info the article states as lacking, is at the end of the video. Excessive you of the pause button will reveal to you that they use an Areca, Adaptec and the onboard controller(s) to achieve a total bandwidth of 2000+ mbyte/second.

All other info you might want about the setup is also there.

Themurph 03/10/2009 7:19 PM
Hide
-0+

@spazoid Good catch, Spazoid! I didn't even see this bit after the video's little celebration.

They're still running quite a strange RAID setup though: using two controllers and onboard motherboard connections to, what, create one giant RAID of drives? Surely there has to be some performance loss from splitting the drive connections up as they do.

Also, -15 points for the "pause to see how we did it" deal. Ugh.

dlapham 03/10/2009 7:20 PM
Hide
-0+

Maybe they were using raid 10 to achieve both redundancy and speed?!?!

nihility 03/10/2009 7:44 PM
Hide
-0+

Watch the video to the end, they tell you exactly which RAID cards they used.

The say they had 10 drives hooked up to a 24 port card, another 8 hooked up to an 8 sata port card and another 6 plugged into the motherboard.

They also state that with the 24 SSDs all hooked up to one card they were getting a serious bottleneck so they instead used the aforementioned setup.

The video is pretty awesome IMHO. When they opened up 54 programs in a bit over 10 seconds it blew my mind.

MasonStorm 03/10/2009 8:25 PM
Hide
-0+

How does one set up a RAID array spanning three different controllers?

hellwig 03/10/2009 8:31 PM
Hide
-0+

MasonStorm :
How does one set up a RAID array spanning three different controllers?


The right software will raid any harddrives connected to the system, regardless of controllers or even interface. I agree with the article that it was probably RAID 0. Any sort of calculation dependant on the CPU would have greatly reduced their throughput.

mapesdhs 03/10/2009 8:41 PM
Hide
-1+


I'll be more impressed when they break past 40GB/sec, speeds SGI
achieved 10 years ago with simple FC.

Ian.

MasonStorm 03/10/2009 8:42 PM
Hide
-0+

Hi hellwig,

What would be some examples of such software, and are there any that would allow such a created array to be used as a boot drive?

MRFS 03/10/2009 9:02 PM
Hide
-0+

> The say they had 10 drives hooked up to a 24 port card, another 8 hooked up to an 8 sata port card and another 6 plugged into the motherboard.

So, the ceiling was not dictated by a single x8 slot (2GB/sec),
but by the PCI-E lane assignments made by the BIOS and the chipset.

What do we get if we go RAID-SLIorCROSSFIRE with 2 x RAID controllers
each using x8 PCI-E lanes, or preferably 2 x8 PCI-E 2.0 lanes.

Highpoint's RAID controllers can be "teamed" in that fashion.

Do we then run into the same ceiling, or not?

Inquiring minds would now like to know.


MRFS

hellwig 03/10/2009 9:29 PM
Hide
-0+

MasonStorm :
Hi hellwig,What would be some examples of such software, and are there any that would allow such a created array to be used as a boot drive?


I doubt you could boot off such an array, its a purely software implementation, meaning something has to be running the software.

That said, I don't have specific examples (never done it myself). Many OSes can implement RAID on their own: http://en.wikipedia.org/wiki/Redun [...] mentations

This article here on Toms tells how to setup RAID 0 or 1 in Windows XP: http://www.tomshardware.com/review [...] e,363.html

This guy claims to be able to hack Windows XP into doing RAID 5: http://www.jonfleck.com/2009/02/24 [...] /#more-934

I'm sure there are third-part apps out there that implement this as well, but I wouldn't know where to look.

mapesdhs 03/10/2009 10:02 PM
Hide
-1+

MasonStorm writes:
> How does one set up a RAID array spanning three different controllers?

For hw RAID I guess it depends on the cards and management sw.

For RAID0, it's easy to do this on certain systems, eg. under
IRIX, using 3 x QLA12160 (6 disks per channel, SCSI controller
IDs 2/3, 8/9, 10/11), optimised for uncompressed HD, it would be:

Code :
diskalign -n video -r8294400 -a16k '/dev/dsk/dks[p0,2,8,10,3,9,11]d[8-13]s7' | tee xlv.script
xlv_make < xlv.script
mkfs -b size=16384 /dev/xlv/video
mkdir /video
mount /dev/xlv/video /video


(I hope the text formatting works for the above)

That gets me 511MB/sec sequential read using a bunch of old/slow
Seagate 10K 73s, on an Octane system more than a decade old. With
modern SCSI disks, I get the same speed with just a couple of
drives per channel.

I should imagine Linux and other UNIX variants have similar
sw tools, but I don't think Windows offers the same degree of
control.

Ian.

fiskfisk33 03/10/2009 10:04 PM
Hide
-0+

why are you guessing what they used?
if you watch the vid in hd and pause at the end you can read it perfectly :P

they had
10 drives connected to an 'areca 1680ix-24'
8 to an 'adaptec 5 series'
and 4 directly to the mobo.

falchard 03/10/2009 11:57 PM
Hide
-0+

Why did they use a Mid-Tower?

graviongr 03/11/2009 1:43 AM
Hide
-0+

I also read all the pause screens, it also says they disabled all optical drives. So you can have a super fast system but you can't watch a DVD lol.

Pointless.

MRFS 03/11/2009 3:59 AM
Hide
-0+

> they disabled all optical drives

Maybe they ran out of SATA ports? :)


MRFS

MRFS 03/11/2009 4:06 AM
Hide
-0+

> they disabled all optical drives

I use that chassis: They let the SSD's "all hang out";
as such there was no need to install them in 24 x 2.5" drive bays.

It could be done, however, with 4-in-1 enclosures
like the QuadraPack Q14, and this Athena unit I
recently purchased from Newegg:

http://www.newegg.com/Product/Prod [...] 6816119006

6 x 5.25" bays @ 4 x SSDs each = 24 SSDs total

That Thermaltake Armor chassis has 11 x 5.25" drive bays:

http://www.newegg.com/Product/Prod [...] 6811133021
(see photos)


MRFS

ossie 03/11/2009 5:19 PM
Hide
-0+

Kind of counterproductive to use 2 expensive HW RAID controllers and SB-SATA for a big array.
A better solution for higher performance and lower cost would have been 3 PCIe-x8 8 port SAS HBAs with SW RAID.

MRFS 03/11/2009 7:18 PM
Hide
-0+

Yes! 3 x x8 PCI-E 2.0 8-port SAS HBAs.

http://www.highpoint-tech.com/USA/rr4320.htm

The RocketRAID 4300 series is a PCI-Express x8 SAS RAID controller that supports up to 8 SAS/SATA hard drives with the industry fastest Intel Xscale IOP348 processor at 1.2 GHz. The RockeRAID 4300 series is effciently maximzed with HighPoint’s 2nd Gen. TerabyteArchitecture™ to deliver the highest sustained transfer rates with over 1004MB/s read and 913MB/s write and maximum data protection. With a PCI-Express x8 interface the RocketRAID 4300 series offers the maximum bandwidth for the highest data transfers.


http://www.highpoint-tech.com/PDF/ [...] asheet.pdf

Multiple card support within a system for large storage requirements


[end quote]

MRFS

MRFS 03/11/2009 7:43 PM
Hide
-0+

ossie,

What motherboard(s) would you recommend for:
3 PCIe-x8 8 port SAS HBAs with SW RAID ?


MRFS

dare jang 03/11/2009 11:28 PM
Hide
-0+

Finaly we got some pepole that will toy with the ssd's and got enough of em.
i read somwere that the ssd does arround 200mb/sec thats a theoretic 4800mb/sec for all the 24 ssd.
pci 8x is like 2000mb/sec if i understand correct.
So what i see is a bottel neck. ssd to system.
Is there enyone here that could sugest a insane interface to the system.
im gussing on some insane priced server board.
i dont know how san's and stuff work or connect to servers.

Question is so. what is the optimal way to get the ssd power into the system?
Do enyone have acces to these kind of hardware?
finaly: can enyone "tube" a video of there test.

Let the nerds have fun. lets get some super tests of ssd's and lets drool.
It will help future enthusiasts to build there systems.

Finally an apolegy those hwo read this far. im danish, hence my BAD ENGLISH.

Current system:

core2duro 3ghz @ 3.21ghz
2 gb croshair ddr2 6400 @ 961mhx
Asus maximus formula.
7800 GTX (clocked too)
4x old samsung 250gb i diferend raid modes

MRFS 03/11/2009 11:53 PM
Hide
-0+

> Question is:
> So what is the optimal way to get the ssd power into the system?


We're just using a standard AT-style PSU from Antec,
in a chassis that holds 2 x PSUs i.e. Cooler Master HAF-932.

If you shop around, there are several manufacturers
who build cases with room for 2 power supplies,
e.g. Lian-Li, Silverstone, Antec, Cooler Master, NZXT.

Those older AT-style PSUs have their own power switch,
so it's very easy to leave the SSD subsystem powered UP,
even if the motherboard is shutdown.


> pci 8x is like 2000mb/sec if i understand correct.

Not quite: "PCI" is the old standard of 32 bits @ 33 MHz
= ~133 MB/second (8 bits per byte).

It stands for Peripheral Component Interconnect.

"PCI-E" is the correct abbreviation for PCI-Express --
the latest standard.

Each PCI-Express "lane" supports 2.5 GHz in each direction:
at 10 bits per byte (serial protocol) that's 250 MB /sec
in each direction. With serial protocols, there is one
"start bit" and one "stop bit" in addition to 8 data bits,
for a total of 10 bits per logical byte (or charter).

So, yes, an x8 lane PCI-Express slot should support READs at
250 MB/sec. x 8 = 2,000 MB/second (theoretical bandwidth,
no overhead anywhere). Call it MAX HEADROOM :)

MRFS

MRFS 03/11/2009 11:56 PM
Hide
-0+

p.s. "(or charter)" should have been "(or character)"
in my last post; sorry for the typo.


MRFS

raysolomon 03/12/2009 9:13 AM
Hide
-0+

This SSD array benchmark makes the $14,000 IODrive look slow.
http://www.sandirect.com/product_i [...] ts_id=1193

mapesdhs 03/12/2009 12:20 PM
Hide
-0+


MRFS,

Don't forget there's also PCI64 and PCIX. My system has a mbd
with proper PCIX/133 (ASUS M2N32 WS Pro) so I get much higher
speeds than 133MB/sec when using PCIX RAID cards (359MB/sec with
just 4 disks). My mbd has a 6000+, but ASUS also has i7 mbds
with PCIX aswell, so I'll be using one of them for my next
build (P6T WS Professional), fitted with a couple of QLA2342
FC PCIX cards which were very cheap off eBay, though I also
have a PCIe U320 RAID card to use aswell.

Personally, I've never understood why supposedly 'enthusiast'
mbds don't include even a single PCIX slot. Strange thing is,
the cost of my mbd was a lot less than many gamer mbds, yet
it works very well (it was 110 UKP, approx. $175 at the time),
currently fitted with an 8800GT (790MHz core).

If you want mad disk speeds, there are other ways to do it than
PCIe, SATA and/or SSDs. For real scalability, FC still cannot
be beaten.

Ian.

ossie 03/12/2009 1:24 PM
Hide
-0+

MRFS, any MB with enough PCIe lanes to the NB (MCH) would do. More difficulties will arise to find one with 3 PCIe x8 directly to the MCH. Skulltrail (D5400X) is one of those few, even if the 32 PCIe 2.0 lanes are bridged through 2 nVidia's nForce 100 MCP's - sadly only PCIe 1.0 support - to 4 PCIe x16 slots.
Intel's S5000P SAS server MBs have only 2 x8 to the MCH and 3 x4 to the ICH (one used for onboard SAS), ICH to MCH being x8. The nonSAS version has three x8, the x4 used for onboard SAS being rerouted to form a x8, but still trough ICH, thus beeing a higher latency way.
Maybe next generation of server chipsets would offer more IO BW with RAM controller being integrated in the CPU.
A problem would arise due to somewhat limited memory (FB DIMM) and CPU (FSB) BW, thus a 24 SSD SW RAID would be pushing the system to it's limits. A more balanced solution would be with at most 16 drives, freeing enough BW for other processes.
Most high-end HW RAID controllers (max PCIe x8 = 2GB/s, haven't seen any native PCIe 2.0 ones) today are pushed easily to their limit (BW) with 8 SSDs. The only metric to be improved with more SSD's would be IOPS and, eventually, write performance.

One interesting research article would be to find out IOPS limit for high-end HW RAID controllers.

ossie 03/12/2009 2:17 PM
Hide
-0+

Ian, currently PCI-X support for legacy HW is through PCIe x4 - PCI-X bridges (PHX670x, etc.), also going through ICH, which just adds latency, BW beeing limited to 1GB/s.
FC HBAs are also connected through PCIe/-X buses, so same limitations apply.
FC has it's architectural advantages (distance on FO infrastructure, availability, redundancy, scalability, security, topologies like switched fabrics, etc.) which are very useful for the enterprise SAN - also incurring high costs - but current Base2 800MB/s BW isn't exactly spectacular as one SAS2/SATA3 channel will get 600MB/s at much lower cost. More impressing is Base10 technology for inter-switch links (at 2.4GB/s).

mapesdhs 03/12/2009 4:20 PM
Hide
-0+


ossie,

I guess that just shows the limits of PC hardware. My mbd uses
the uPD720404 which is as you say a PCIe 4-lane bridge, though
I don't know whether it has one chip per slot or just one for
both (probably the latter).

If one wants to do this sort of thing properly, it's hard to
beat decent UNIX-based systems. SGI's IX-brick has twelve PCIX
slots split across six separate buses, so it can feed all of
them at good speed (total bandwidth through the three bridge
ASICs of 7.2GB/sec). Their newer Altix series does of course
have PCIe bricks aswell with oodles of slots.

Ian.

MRFS 03/12/2009 7:33 PM
Hide
-0+

G-R-E-A-T contributions, everyone!

I've learned a lot from your recent comments above.

Encore! Encore!!


MRFS


Comments are closed on this page.

Sponsored links