Fortysomething Geek

I decided to upgrade my Drobo 5D; replacing all five 3TB Seagates with five new 4TB Seagates.




I now have 14.5 TB of real useable space; using 4 Terabyte drives. I offloaded my 4 month old 3TB drives into a cheap 4 bay eSATA RAID box. That right there is another 9TB to play with under RAID5.

I also tried the LaCie 2big and it shows up in the device manager as drives but since they are in Mac software RAID, I could not mount them. I didn't want to reformat my drives but the drives checked out fine in Windows 7.

Sadly, the new Drobo 5D will not work with Windows via Thunderbolt.

Drobo has posted the following:
http://support.drobo.com/app/answers/detail/a_id/677/~/windows,-thunderbolt,-drobo-5d-%26-drobo-mini

USB 3.0 works on the Drobo 5D just fine. This is a major bummer for those looking to use the Drobo in Windows. This may change in the future.

Thunderbolt mini-Displayport works but I could not do a iMac Target monitor connecting to a Windows machine. Next, displayport via Thunderbolt only works with Intel integrated GPUs. On the Ivy Bridge models, it is the HD4000. I could not get my Kepler Nvidia GPU to pipe the display out to Thunderbolt.

I've had some time to play with the Drobo 5D; filling up about 6TB worth of data (out of 10.89TB in my 5X3TB setup). I've been using it in a mix-use environment. I think I have enough time to form an opinion. So here is my non-professional, regular end-user hands on review of the new Drobo 5D Thunderbolt / USB 3.0 raid box.

Introduction

The device was originally announced during the summer and there was a series of delay, waiting and anticipation. Drobo did not release performance figures until they neared shipping. This was not a very promising introduction.

I was ready to give up and go elsewhere. The Pegasus R4 is the closest competitor to the Drobo and I'm sure it will be cross-shopped. The Pegasus R4 (4 bay RAID) system can be had for 1,000ドル with 4TB of disks (985ドル at Provantage link, 1100ドル amazon link).

The Drobo 5D is 850ドル and it comes bare (enclosure-only) but does include a Thunderbolt cable (which is worth 50ドル by itself). You will need to load it up with drives. If you are a savvy shopper, you can start off with three 2TB drives to give you 3.63TB of useable data (according to the online calculator) to match the Pegasus R4's storage capacity. So if you shop around, three 2TB will cost about an 300ドル (with heavy slickdeals-like discount and bargain hunting) which still makes it more expensive than an R4 setup.

Even though the Drobo 5D is more expensive (with drives), you do have 5 bays vs R4 only having 4 bays. You also have the added benefit of USB 3.0 which the R4 lacks. This broadens the use of this device over a Thunderbolt only system. With 5 bays, you have the potential of filling it up with 4TB drives; giving you around 14.5TB useable storage (from 16TB). That in itself is very compelling.

You can start off cheaper with a Drobo because you can add drives at any time. But, I doubt anyone buying a Drobo at 850ドル will skimp out by using 1 or 2 drives.

So why would I go out and buy this device? Well, I was already allotted a budget and "gifted" funds to buy one from a job I did over the summer. In short, I had to buy one or return the bonus funds I got from that job.

The Drobo Sales Pitch
Drobo claims this device will yield 400 MB/s reads with 256 MB/s writes on average. That doesn't sound as compelling as their competition who posts higher Megabytes per second. Rather, Drobo prefers to bench based on I/O per seconds (IOPS). They believe that "real-world" performance is where the 5D will shine.

They explain this in detail on their performance page: http://www.drobo.com/how-it-works/performance-professional.php

In short, they claim:

"While benchmarking give you a good indication of how well a storage device performs when it’s healthy and for a single task, it is still not a replacement for real-world performance. Benchmarks are nice, but real-world performance is everything."

Real-world performance includes a mix workload; copying various random small files in addition to large bulky files. This is where the IOPs figure comes into play. If you are copying a Photo Library folder with lots of small thumbnails or large volumes of small text files (say a web project), your transfers will be slower than if you normally copy something like large video files. I've seen this happen in the real world where I copied GIT repo of a website with thousands of files and it did indeed take longer than copying large movie files.

They claim 400 to 1280 IOPS. For comparison, some single SSDs are rated at 40,000 to 80,000 IOPS. The Samsung 830 SSD has benched 4K random read IOPS of 80,000.

Other HDD manufacturers do not bench on IOPS and I could not find any reviews on the net to compare the Drobo 5D to when it comes to comparable storage/raid redundancy.

If you are used to thinking in Megabytes per second, you need to acclimate yourself to IOPS.

The Drobo uses a form of RAID which is similar to RAID5/RAID6/RAIDZ. They call it Beyond Raid and it has a some unique characteristics both real and perceived. It provides single or dual disk redundancy. This in itself is very important. This is a redundant RAID system.

Unlike traditional RAIDs, you can mix-and-match drives sizes (called Mix drive utilization). You can also grow your array at any time buy swapping out smaller drives for larger ones. You can start off with 1TB drive, add 2TB in a few months, or opt to mix and match with 3 and 4TB drives as prices drop. This provides un-paralleled flexibility.

Unlike other RAID systems, Drobo implements their version of data-tiering. Tiering, not to be confused with SSD caching, basically will automatically stores the files that require faster access on SSDs. The system automatically tunes itself and migrate data across SSD/HDD depending on usage. This is similar to the "Fusion" drive technology that Apple recently announced for their new iMacs/Mac Minis. Like the Apple's Fusion drive, the Drobo requires an SSD in the form of a mSATA drive that is installed in the bottom bay. This is the key to increasing IOPS performance.

Their pitch on data-aware tiering can be found here: http://www.drobo.com/how-it-works/data-aware-tiering.php

Using SSDs for acceleration, smaller and random reads benefit significantly while the larger HDDs are used for storing larger data. This whole process is automated. Transactional tiered data goes to SSD and bulk data goes to platter drives. I can see the benefits for databases and virtual machines.

For a non-technical person or someone unfamiliar with RAID technologies, the Drobo 5D is a simple and easy to use system. In theory, you can't go wrong. You won't get the fastest drive setup but you will get ease-of-use and a rich feature-set. Automated data-tiering is a very compelling proposition.

The things I like

• Battery backed cache. This is found in more expensive RAIDs and helpful in case of power failure.
• The software has a nice GUI interface with tools like email notifications.
• Two Thunderbolt ports for daisy-chaining and it does indeed work well.
• Black thunderbolt cable that is slimmer than Apple's cable. Where can I buy another?
• Ability to mix drives and upgrade in the future.
• Thin Provisioning.
• Ability to boot from Drobo.

The Competition


As I wrote earlier, the Pegasus R4/R6 are the closest competitors to the Drobo 5D. The Pegasus R4/R6 yields 635 MB/Sec read 535 MB/sec writes. R6 averages both 680 MB/sec read/writes.

Testing


Let me preface by saying I am NOT a professional journalist or reviewer. I am enthusiast end-user and a normal consumer like you.

My source drive is a Crucial M4 512GB SATA 6.0Gb/s running on a Macbook with Mountain Lion 10.8.2. The Crucial M4 random reads bench at 45-50,000 IOPS (http://techreport.com/review/20646/crucial-m4-solid-state-drive).

In short, my source copies will not be bottlenecked copying to the Drobo.

My Drobo 5D setup:

• Five Seagate ST3000DM001 3TB 7200 RPM 64MB Cache SATA 6.0Gb/s
• Crucial M4 mSATA 6gb/s 128GB SSD w/ latest firmware 01MG as the cache accelerator drive

My set-up gives me 10.89TB useable space (15TB of drive, actual size 13.64TB).


Knowing that the Drobo 5D will not bench that great using MB/sec, I attempted to evaluate this device on Drobo's premise of mix-real world usage. However, I will also present synthetic Black Magic numbers for reference.

Next, Thunderbolt. the best I could muster over several tries were 210-240 MB/s writes and 290-300MB/s reads. This is actually good for a consumer RAID but fall short when compared to something like the Pegasus R4.


Again, these are just synthetic numbers that an application produces and is not indicative of real-world use. Im not a professional reviewer so I can't give you IOPs numbers.

To follow Drobo's assumption of real-world mix usage, I attempted to see how well it performed copying a mix of different file types.

Instead of trying another synthetic test, I did it the old fashion way. I timed it. My test is all writes. I am more concerned about fast the drive writes my copy rather than how fast it reads.

Instead of copying large 30GB files to see the sustained transfer rate, I opted to try a typical usage of copying my photo backups. This s a 28.76GB folder of 2,277 photos in RAW format from my DSLR. This is 2-3 months of photos and typical usage example to test performance of copying a lot of medium sized files where the should Drobo shines.

I called this the Photo test.


I did another test with extremely small files. A webserver folder with 27,759 items clocking it at 1.5GB. These include small 5k HTML/Javascript files. So this would be a typical thing for a web developer to back up his/her files of a working project.

This is the WebTest.

• Samsung 830 SSD via USB 3.0 in an Oyen Mini-Pro enclosure (with ASMedia 1051e chipset).
• Samsung 830 SSD w/ Seagate Thunderbolt Adapter
• Internal Seagate Momentum XT 2.5 " 7200 rpm drive. This is the Hybrid XT drive.
• 5400 rpm USB 3.0 Seagate Go Flex portable drive
• 5400 rpm Firewire 800 Seagate Go Flex portable drive
• USB 3.0 Hitachi portable 2TB drive. 5900 rpm.
• HDD Thunderbolt comparison against a LaCie 2Big 4TB in RAID 0.

Conclusion

You need to heavily weigh your needs and your usage to consider this device.

Filling up a Drobo is not cheap. 5x 2TB drives would cost you around 500ドル (if you can get the drives at 100ドル a piece) and this would yield you 7.26TB of usable space according to their drive calculator.
Dont even bother with 1TB drives. The difference being 70ドル vs 100ドル 2TB on sale, go for the 2TB or 3TB HDD drives. Hence, we are now talking about around 1350ドル to begin. This does not include the mSATA cache accelerator drive. With a 128GB mSATA cache drive, you are looking at 1500ドル.
1500ドル can buy you lots of drives, SSDs, and even a few RAID enclosures.

As for a redundant backup system, you may want to skip the Drobo 5D because I do believe the 850ドル is a bit pricey for that type of use. If you absolutely need to have something faster than your current backup system, then the Drobo 5D may be an option for you.

As for a performance oriented work drive, it is a tough call. The Pegasus R4 is a proven performer with little problems (according to end users and message boards). You can buy an R4 for your fast RAID5 and a few external USB 3.0 3TB drives for your secondary backups. Or you can buy a LaCie Big Disk (I got a 4TB refurb for 200ドル) and a lot of spare 3-4TB external drives.

The picture below exemplifies this hard choice. 900ドル can get you a LaCie 2big, 2 SSDs, three 3TB USB 3.0 external drives (totaling 9TB) vs an empty bare Drobo 5D enclosure (with no drives). 13TB vs 0 on the Drobo.



For me, it boils down to this, how big of a scratch work drive do I need? If you need 6 TB and larger, the Drobo is a good buy.

There is no substitute for the fact you can get up to 16TB of storage with good speed. 200-350 MB/s is still very good.

If you are looking for a combination of both in terms of mix-use (backup drive and work drive), then you might buy the sales pitch Drobo is making.

As for me, I think a mix-setup that I currently have is more preferable: A fast 4TB cheap Thunderbolt striped RAID or SSDs for work disk and a NAS for backup along with multiple external drives/cheaper RAID setups.

If the Drobo 5D was 100ドル-200ドル cheaper, I would totally recommend it.

I'll probably end up keeping this device. I can always use the storage.

Update 2012年12月03日: Thunderbolt does not work under Windows. Read more on my blog post.

The Drobo 5D is the first dual USB 3.0/Thunderbolt RAID system from Drobo. It had a long anticipate wait, but now I have one in my possession. Was it worth the long wait? Lets see!

This is a first look at the newest Drobo. I will follow up with a more comprehensive take/review later.