OCZ Core V2 SSD drives in RAID = AWESOME

vbimport

#1

SSD drives are fairly new, they are currently quite expensive and, they have only recently entered into the mainstream market.

Currently there are two types of SSD drives sold as complete products.

SLC (Single level cell) these are high performance and high price, they generally also have a fairly large cache (64MB) is not uncommon. Prices range from about £400 for a 32GB model to several thousand for higher capacities. Generally speaking, SLC based drives are aimed at the enterprise storage market, where high performance and reliability is a must.

MLC (Multi level cell) these are once again high performance, in fact, very often faster than their SLC counterparts when reading. They are aimed at the mainstream/enthusiast market. Prices start at around £90 for a 32GB model. MLC drives do have some shortcomings. Most of the MLC based SSD drives are generic and are built on a JMicron controller with Samsung MLC NAND flash memory. They also in most cases, have very little cache compared to their SLC counterparts. Although no one is prepared to give clear details, it is suggested the cache on MLC based SSD drives is as little as 256KB.

MLC also has latency problems when small random files have to be written to the drive. The problem can be quite noticeable because many of these small random files are written in the background by the operating system. The problem manifests itself by making the PC pause or stutter, from a fraction of a second to several seconds.

So how can we eliminate the pausing and stuttering?
This was actually quite easily solved, but at a price. A hardware RAID card with onboard cache is required. These are fairly pricey. They start at around £100 for a PCIe x1 card with 128MB of onboard cache and a Marvell 400MHz ROC (raid on a chip). Don’t be fooled into thinking you can fit a cheap so called RAID card. They simple won’t solve the pausing and stuttering problem and the motherboards onboard SATA/RAID ports are simply not fast enough.

A PCIe x1 card is fine for a single SSD drive. If you want to add a second SSD and intend to have them setup in RAID 0 (stripped) then a PCIe x1 card won’t be fast enough. Remember a PCIe x1 lane has only 250MB/s bandwidth, without considering overheads.

What is really needed to allow a couple of fast SSD drives to breath and break free is a hardware RAID card with onboard cache and, using a PCIe x4 or x8 interface. With a fast ROC (raid on a chip) and 128MB of onboard cache and all importantly, using a PCIe x4 or x8 interface, you should have a around 1GB/s bandwidth on a x4 PCIe card and around 2GB/s bandwidth on a x8 PCIe card.

This may seem like overkill?
Well no, it’s already becoming clear that SSD drives can very soon saturate a system bus. Remember, compared to a traditional hard drive, they have 10 to 30 times less reading latency. There is also no fall off in performance as the SSD read and writes, unlike a traditional hard drive where performance is really only fast for large files located at the start of the disc surface. When a traditional hard drive nears the centre of the spindle, performance can be only one third of the speed. SSD drives do not suffer from this; the reading and writing speed is equal throughout the drive.
SSD drives also scale much better than traditional hard drives in a RAID 0 configuration, having two traditional hard drives in RAID 0, does not give you anywhere near double the performance, whereas, adding two SSD drives in RAID 0 more or less doubles the performance, providing the RAID card is up to it.

Below is a result from a PCIe x1 hardware RAID card which simple can’t cope with the amount of data these two SSD drives can supply.

The restriction on bandwidth on a single PCIe lane holds back the reading performance very badly. Now compare with the results of the same two drives on a x8 PCIe card (8 PCIe lanes).

Okay, let’s see some results from a couple of MLC based SSD drives connected to a fast PCIe x8 hardware RAID card with onboard cache.

System
GigaByte GA-X48-DS4 (X48 chipset) motherboard
Intel Quad core CPU (Q6600) @2.4GHz
4 GB of OCZ Platinum PC6400 (4-4-4-15 timings)

RAID setup
Adaptec 2405 4 port unified hardware RAID, SAS/SATA (PCIe x8 interface).
Intel dual core ROC (raid on a chip) clocked at 800MHz.
128MB of write-back cache (DDR2 with parity checking).

Windows Vista Home Premium 64 Bit is installed and running from the SSD RAID setup.

2x 64GB OCZ Core V2 MLC drives in RAID 0

We will start off with a few benchmarks

HDTach reading performance test (large files 32MB zones)

282MB/s reading speed is very impressive.
Also note the access time of 0.3ms
Burst rate is also extremely good at 675.1 MB/s

HD Tune file benchmark (64MB file length)

OK it’s very impressive, but really only showing the grunt of the RAID card when reading.

ATTO disk Benchmark (256MB file length)

This time we see the true file reading and writing performance of the SSD drives, as the file length is larger than the cache.
Reading speed tops out at 250MB/s and writing speed tops out at 200MB/s
Very impressive.

So, how does the system feel and what is it like to use, using this SSD RAID setup?

Well, let’s just say, it brings using the PC to a completely different levels. Applications load in an instant, saving large files in an instant and, all in complete silence.

So how much does this all cost?
Well it isn’t cheap.
OCZ Core V2 64GB £129 each
Adaptec 2405 RAID card, around £179 (retail version)
Total = £437

I would really like to hear your views on this post and this setup, would you be prepared to spend this amount of money for this type of performance?

Do you have a traditional hard drive raid setup that can outperform this system? Let’s see it.

Do you have an SSD drive yourself? Let’s see some results.


#2

Thanks Dee, great reading :flower:

I’d definitely spend the money if I had it to spare, to soup up my main review PC. :iagree:


#3

If money wasn’t [B][U]the[/U][/B] problem, i would have spend the money for this performance, but for the moment i’ll have to live (and be miserable) with my current HDD’s.


#4

That sure is impressive performance from that SSD RAID setup! :clap:

Would I use that kind of money to get that performance?
With my current needs probably not, especially since I switched to using a Small Form Factor computer as my desktop computer.

I can certainly see the attraction of that kind of performance, and it sure looks tempting!

Thanks for showing us how great an SSD RAID setup can be. :flower:


#5

Just shows that the second 16x PCIe on your motherboard can be used for something more useful than a SLI or Crossfire graphics card setup. I can’t see a pair of SSD drives being beaten 6 months later by a single drive costing half the price.

Dee, will this new setup be permanent, or are the drives only on loan and will have to go back eventually? :sad:


#6

@Ibex

I think Dee paid for all that stuff.

Well it isn’t cheap.
OCZ Core V2 64GB £129 each
Adaptec 2405 RAID card, around £179 (retail version)
Total = £437


#7

Yes, the RAID SSD setup is my own. I was saving for an Intel i7 system, but when i learned of the price of the new Intel CPU and everything else that was required to upgrade, i decided to purchase the SSD system instead.

Would anyone like to see some more tests on the SSD RAID setup? Name the test and i’ll try to do it.


#8

[QUOTE=Dee-27;2154829]Yes, the RAID SSD setup is my own.[/QUOTE]

I couldn’t be happier for you, enjoy. :clap::clap::clap:

Thank you for sharing this with us, a very interesting article. I am impressed with the amount of research that you obviously put into this purchase.

I have just been reading a review of Intel’s new X25-M SSD. Its 10 parallel channel design gives an average read speed of 226MB/s, impressive for a single drive but still slower than your pair of drives. And with the 80GB standard drive costing an eye watering £520 (160GB & server models also available) your setup beats it on value for money as well.


#9

All I have to day Dee is [B]AWESOME. [/B]The future is here, you have proved that beyond any doubt.:clap:


#10

Beautiful Review … now the biggy, how does a single SSD drive compare with a VelociRaptor 10K for real world :smiley:

I’ll note that there have been huge progresses in the linux community for booting the OS in under 10s … although the definition of the usable OS is pretty slim - it gives you a working window manager & network interfaces were thrown out the window :stuck_out_tongue:

And the definition of “booted” is that everything is loaded and the HDD is stationary - although, with SSD’s, how could you tell :wink:

The other problem I see with the SSD’s is the limited size … although with all the huge (cheap) mechanical drives system builders could always bundle a large capacity 5400RPM drive (like the WD Green series) in the system with an SSD boot drive.

I doubt 90% of the general population would ever really use more than 64GB in the next few years.
My parents have had an 80GB HDD for almost 4yrs & have filled about 20GB with photo’s and email (besides the OS).

Ok, I propose a final test for SSD’s … the defrag! J/k :wink:

Although I’d also love to see if there is any real performance difference in regards to network file sharing. I’ll note that with a simple file server running XP pro (gigabit ethernet), there are often long delays accessing files. Does the SSD make any tangible difference, or is are the delays simply due to the Ethernet, or the OS?


#11

Dee really this is very impressive - very good presentation of envious material :slight_smile:

What i would really like to know - but unfortunately not up to you to present - is how does this configuration compare to a raid of two of the new velociraptors - always with aspect with the expense difference.


#12

This page here shows some RAID 0 VRaptors. For lazy people the results were with HDTach.

Read Tests
Burst 156
Average 198
Maximum 234
Minimum 148

@Dee my question is with multitasking do you ever run into any shuttering problems, did the RAID card eliminate it completely?


#13

I don’t have a RAID setup yet but considering getting a RAID card. I wonder if we can use one card for multiple RAID setups. For example, an 8 port RAID card, two ports for RAID0 setup for OS/applications and other ports for RAID5 for data?


#14

Thanks everyone for the comments.

@debro. I would think an SLC SSD would do as good as a single Velociraptor in “real world” if connected to on-board SATA. I would think most MLC drives would do worse than a single Velociraptor when connected to on-board SATA. But i think both SLC and MLC SSD (single drive) if connected to a good hardware (with cache) RAID controller would beat the Velociraptor in real world.

Also, the above SSD setup beats 2x Velociraptor (RAID 0) quite easily (performance wise) according to the review that bjd223 links too. :smiley:

[QUOTE=bjd223;2156574]@Dee my question is with multitasking do you ever run into any shuttering problems, did the RAID card eliminate it completely?[/QUOTE]I just ran…
TMPG 4 Express, encoding a large MPEG2 file
Played some music.
Browsed the Internet
Checked email
Chatted on MSN.
All at the same time, no problems at all. But that is why i wanted a hardware RAID card to run these SSD drives.

@zaina
Yes. you can run multiple arrays on the Adaptec cards and i would imagine most other hardware RAID cards. But for a good 8 port (PCIe x8 card) your looking at serious money. http://www.adaptec.com/en-US/products/Controllers/Hardware/sas/performance/SAS-5805/

Add to that a X48 m/board as well for true, twin x16 PCIe support. Otherwise, adding a x8 PCIe RAID card will slow your graphics card down to x8 as well.


#15

[quote=Dee-27;2156641]Add to that a X48 m/board as well for true, twin x16 PCIe support. Otherwise, adding a x8 PCIe RAID card will slow your graphics card down to x8 as well.[/quote]You’re right and I just checked my mobo manual it says “The speed of the primary PCIe x16 slot changes to x8 mode after you install [B]any device[/B] in the secondary PCIe x16 slot.” Not good. So that means even if I get x4 RAID card my video will downgrade to x8.

Do you know what kind of performance comparison on x8 vs x4 RAID card? Is it much faster? how about with x1 RAID card, since I have an extra PCIe x1 slot. Do you think it’s worth it?


#16

[QUOTE=zaina;2156654]Do you know what kind of performance comparison on x8 vs x4 RAID card? Is it much faster? how about with x1 RAID card, since I have an extra PCIe x1 slot. Do you think it’s worth it?[/QUOTE]Lets put it this way. I made the mistake of getting a HighPoint Rocket RAID 3120 in the first place. It’s a hardware RAID with a Marvell ROC (raid on a chip) clocked at 400MHz, 128MB of cache running on a PCIe x1 interface. It could only handle one of these SSD drives.

Lucky for me, the vendor i bought it from was prepared to part exchange it for the Adaptec card. I’m unsure if the limitation of the HP RR was down to the ROC performance or the restriction of the card being PCIe x1. I suspect a bit of both.

For an 8 port card, i would strongly recommend at least a PCIe x4 card, with at least a dual core ROC clocked at 800MHz and 256MB of cache.


#17

A very nice read, really enjoyed it, would probably go for an Areca PCI-E RAID card, have owned a couple, and find they are hard to fault, a bit more expensive that others, but just work well.


#18

Thanks Dee! Fantastic post - am def considering spending the money on this instead setup of upgrading to an i7 platform and keeping my old discs.

One confirmation though: Are you sure £129 isn’t for the normal OCZ Core 64gb ssd, not the ‘V2 60Gb’ one? I can only find the V2 starting at £160.

Where did you see the ‘V2’ ones for £129?


#19

Hi :slight_smile:
Very interesting Dee.
Definitely the future.
How about write speed though?
SSD is still comparatively slow.
For around £88 inclusive (Almost 1/5th of the cost). You have the below performance.

CPU Type QuadCore Intel Core 2 Quad Q9550, 2833 MHz (8.5 x 333)
Motherboard Name Gigabyte GA-EP45-DQ6 (2 PCI, 1 PCI-E x1, 2 PCI-E x4, 2 PCI-E x16, 4 DDR2 DIMM, Audio, 4 Gigabit LAN, IEEE-1394)
System Memory 8192 MB (DDR2-800 DDR2 SDRAM)
Storage Controller Intel® ICH8R/ICH9R/ICH10R/DO SATA RAID Controller
Disk Drive Volume0 (931 GB, IDE)[Maxtor DiamondMax 22 SATAII 500GB 32Mb Cache Hard Drive <8.9ms 7200rpm - OEM
X2]

Drive C:

For easier comparison.

Also for another £88, Drive D:

HDDTune (to compare with link posted by bjd223).
Note the 100% CPU usage is due to other tasking running at same time. :eek:


#20

[QUOTE=Toxtoth;2161652]One confirmation though: Are you sure £129 isn’t for the normal OCZ Core 64gb ssd, not the ‘V2 60Gb’ one? I can only find the V2 starting at £160.

Where did you see the ‘V2’ ones for £129?[/QUOTE]I bought mine from OCUK @ £129, but they were on special and i also had a 6% off coupon. They haven’t been in stock for more than 2 weeks though. :frowning:

[QUOTE=zebadee;2161687]Hi :slight_smile:
Very interesting Dee.
Definitely the future.
How about write speed though?
SSD is still comparatively slow.
For around £88 inclusive (Almost 1/5th of the cost). You have the below performance.
[/QUOTE]Write speed peaks at 200MB/s sustained is around 183MB/s
Sustained speeds don’t really mean that much anyway in real world use. In real world use, as seen in the PCMark Vantage results, SSD (on hardware RAID) leave traditional harddrives for dead.

Traditional harddrives (in RAID) also take up a lot of room and make lots of heat and noise. I can fit 3 of these SSD drives in a single 3.5 inch hard drive bay and they are completely silent and produce next to no heat. :slight_smile:

Anyway, here are sustained read and write graphs from H2benchw.