2 WD Black RAID 0 vs 1 SSD?

[simplymuzik3]

Will the speed be comparable between a RAID setup that uses 2 x 1TB 64MB cache Blacks, vs 1 SSD (Intel X25-M for example)? Will the difference be noticeable at all (during application launches etc). I would like to know soon because I just ordered the 2 Blacks, and I just want to be sure I made the right decision!

Thanks,

[robvas]

The SSD will still be way faster for random access. Not to mention the fact that if you lose on disk in RAID 0, you lose everything.

[Transporteur]

The SSD will be considerably faster by all means.
What makes application loading fast is the random access of small files, not high substantial transfer rates.

Anyhow, a single high end SSD would still be faster than a striped array of two 1TB Blacks in substantial reading transfers.

[simplymuzik3]

The SSD will be considerably faster by all means.
What makes application loading fast is the random access of small files, not high substantial transfer rates.

Anyhow, a single high end SSD would still be faster than a striped array of two 1TB Blacks in substantial reading transfers.

Is there anywhere that compares the random read speeds between the 2? I've been googling around and haven't really found any. They're mostly for the velociraptors and higher end drives.

EDIT: Maybe a better question would be: What are the random read times using WD Blacks in RAID? Would they reach 180 MB/s? And what block size would you recommend for a main OS? 32K? Sorry about all the questions!

[jav6454]

Take the SSD, you eliminate the fail factor.

[alphaod]

Take the SSD, you eliminate the fail factor.

No you minimize the loss of data to one disk; SSDs can fail and RAID 0 setups are just as likely to last years without any hiccups.

[simplymuzik3]

Take the SSD, you eliminate the fail factor.

But then you're limited with storage and it also costs more. I already have extra drives for time machine and I regularly do SuperDuper backups. RAID seems to be more cost effective and Im hoping it will yield similar speeds. I currently have a X25-M 80GB in my MBP, and the performance has also degraded quite a bit, I now get 180MB/s, which is why I was asking if the RAID could also achieve those speeds.

I was also thinking about waiting and getting an Intel G3 when they come out. But then you also have to worry about cost, size, and no TRIM.

decisions, decisions...

[Giuly]

Two WD VelociRaptors (http://www.newegg.com/Product/Product.aspx?Item=N82E16822136555&cm_re=VelociRaptor-_-22-136-555-_-Product) in RAID0 are at least comparabile to SSDs in terms of speed, but offer 5x the space for the same money.
Even faster are 15000RPM SAS drives (http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&N=40000014%20600003343&IsNodeId=1&Description=SAS&bop=And&Order=PRICE&PageSize=20), but the controller (http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&N=100007607+600022629+600022672&QksAutoSuggestion=&ShowDeactivatedMark=False&Configurator=&IsNodeId=1&Subcategory=410&description=&Ntk=&CFG=&SpeTabStoreType=&srchInDesc=) (at least one which is bootable on a Mac) costs as much as a 240GB SSD. Apple has a RAID Card (http://store.apple.com/us/product/MB845Z/A?mco=MTY3ODQ5OTY) w/ SAS, too.

[simplymuzik3]

Two WD VelociRaptors (http://www.newegg.com/Product/Product.aspx?Item=N82E16822136555&cm_re=VelociRaptor-_-22-136-555-_-Product) in RAID0 are at least comparabile to SSDs in terms of speed, but offer 5x the space for the same money.

I was looking around google, and people say the VelociRaptors aren't worth the extra money when compared to the Blacks. I know they WILL be faster, but it's just not worth the big price difference. Also, I found some people saying that you wouldn't notice the speed difference in real-world use.

[barefeats]

I use SpeedTools.com's QuickBench to do small random transfer testing on SSDs and HDDs.

The SSD from OWC averaged 143MB/s random read and 125MB/s random write.
The single WD RE4 Enterprise 2TB HDD averaged 26MB/s random read and 96MB/s random write.
The single WD Caviar Black 2TB HDD averaged 27MB/s random read and 74MB/s random write.

I haven't tested dual WDs in a RAID 0 yet but I will before today is over. However, the random read speed will be 50MB/s at best (or one-third that of the SSD).

Another factor to consider is latency. The SSD has virtually zero latency with no moving parts. And it doesn't have to spin up when its put to sleep.

However, there is something to be said for having 4TBs of HDD for the price of of 256G of SSD.

[simplymuzik3]

I use SpeedTools.com's QuickBench to do small random transfer testing on SSDs and HDDs.

The SSD from OWC averaged 143MB/s random read and 125MB/s random write.
The single WD RE4 Enterprise 2TB HDD averaged 26MB/s random read and 96MB/s random write.
The single WD Caviar Black 2TB HDD averaged 27MB/s random read and 74MB/s random write.

I haven't tested dual WDs in a RAID 0 yet but I will before today is over. However, the random read speed will be 50MB/s at best (or one-third that of the SSD).

Another factor to consider is latency. The SSD has virtually zero latency with no moving parts. And it doesn't have to spin up when its put to sleep.

However, there is something to be said for having 4TBs of HDD for the price of of 256G of SSD.

Is it really that much slower with a RAID setup :eek: I thought they would at least be comparable! In real-world use, is it THAT noticeable between a single SSD and RAID? From what I've gathered, it doesn't seem to be THAT drastic!

[jav6454]

But then you're limited with storage and it also costs more. I already have extra drives for time machine and I regularly do SuperDuper backups. RAID seems to be more cost effective and Im hoping it will yield similar speeds. I currently have a X25-M 80GB in my MBP, and the performance has also degraded quite a bit, I now get 180MB/s, which is why I was asking if the RAID could also achieve those speeds.

I was also thinking about waiting and getting an Intel G3 when they come out. But then you also have to worry about cost, size, and no TRIM.

decisions, decisions...

A 80GB drive is going to slow down if it's your main drive. Remember, bigger SSDs won't slow down over time.

Also, you have to ask yourself what this is really for. Is this for storage or for a fast boot? After you answer that, I think you can pretty much have an idea what you need.

[bluesteel]

I was looking around google, and people say the VelociRaptors aren't worth the extra money when compared to the Blacks. I know they WILL be faster, but it's just not worth the big price difference. Also, I found some people saying that you wouldn't notice the speed difference in real-world use.

look at this review and tests including the 600GB Velociraptor, WD Caviar Black 2TB, WD Black RE4 2TB, and Seagate Constellation ES 2TB:

http://www.storagereview.com/western_digital_velociraptor_review