Chuck Hollis over at EMC stirred up a hornets nest with his "Your Usable Capacity May Vary" blog today. Seems EMC is touting its storage efficiency superiority over rivals NetApps and HP by publishing the results of an in-house efficiency comparison. Let’s set aside, for a moment, the fact that Pillar was the first storage vendor to take up the storage efficiency discussion, way back in early 2007, and welcome EMC and NetApps to the discussion...

Let’s also set aside the irony that this is the same EMC that finds it absolutely acceptable that their Clariion customers are currently only utilizing an average of 30-40% of the storage capacity they purchased. For as much as I love a good competitive bake-off, especially when it comes to overall storage efficiency, how can you promote the efficiency of your disk array when you don’t address the most fundamental question storage administrators should be asking... “Exactly how much of the storage I just purchased can I actually use?” (More on that later)

There are many different ways to frame a ‘like to like’ comparison, and when it comes to Storage Efficiency, Pillar leads the pack on most of them. In prior posts I have addressed some of these frameworks. In future posts, I will address more. For now, let’s focus on what EMC tested, the results they published, how Pillar compares… and then, and perhaps most importantly, offer an alternative solution that is easily 2X better than what EMC, NetApps, or HP has to offer.

Table per Hollis’ format. I don’t like this format, but to avoid confusing everyone by flopping it around, this is apples-to-apples with his Blog presentation. Except: we don’t need to add drives and segregate SNAP, Vault, etc with Axiom. Thus – we get the same spindle count for performance as EMC and anyone else (actually more, but that too is another blog entry).

Pillar’s Axiom Application-Aware storage array nails a 75% efficiency score because there is no overhead for such things as WAFL (NetApps), Vault Drives (EMC), or Occupancy Alarm (HP). All system persistence information is kept and mirrored across all drives within the Axiom and is accounted for in the Usable Space from the 120 – 146GB drives. So, we get 75% vs EMC’s 70%, HP’s 48% and NetApps 34%.  Of companies noted in Chuck’s blog, I think this kicks some buttski. Nice, thanks for bringing it up Chuck (hee hee).

Now that we have established that Pillar is more efficient than the other arrays using this approach, let me say that it is really a shame. In other words, the premise of Chuck’s entire blog is an EMC view of the world – FC is how you should skin this cat using their machine. Yup, it is.

But not with Pillar. We can do this for less money, give you the same performance, and FAR greater capacity. Period. Please read that again, cause this ain’t marketing crap – this is a fact.

First, why do we need 120 drives for Exchange? That’s a massive amount of capacity. Not to mention that Chuck is using a drive type, 146GB Fibre Channel, that just got EOL’d by the drive manufacturers. Your only real options today are 300GB 15K FC and 450GB 15K FC.

Also, 17TB is a huge system for an Exchange implementation. But we need the SPINDLE COUNT, not the capacity, and enough spindles on 146 GB drives gets you 17TB. Forget about the fact that using 300GB drives you will net 34TB useable, and 80% of that gets thrown out.

Well, if we are just going to start throwing away capacity, why are we throwing away the expensive stuff? 15K RPM Fibre Channel drives aren’t cheap. You are buying the Dom Perignon of drives, taking a proverbial sip and throwing out the rest of the bottle! If I am going to be forced to throw out a bottle of something, why not make it Chandon? Chandon is a good Champagne, but not quite as expensive as Dom. And yes, Chandon is another word for SATA.

“But SATA is sooooo much slower”, you say? Yes it is, but not in a RAID 10 configuration. Before some wisenheimer spouts off about the read ops being lower in the Table below, remember that Write Ops will completely dominate the solution. Another way of stating this: Read Ops are not a problem with either FC or SATA.

Notice that SATA in RAID 10 performs the same as Fibre Channel 15K in RAID 5. And since you were just going to THROW OUT the rest of the capacity, mirroring doesn’t seem like such a bad idea to get the IOPs. And did I mention that SATA 500GB drives are like 70% cheaper than 15K Fibre Channel drives?

And finally, the last question is… ”Why throw away the excess capacity?”

Well, ya got to throw it away so as not to impact the performance of the Exchange database with Clariion, NetApps, or EVA, in fact in any typical storage array. But not so for Pillar. Pillar’s industry unique Application-Aware architecture allows its customers to create profiles for applications (like Exchange, SQL, File Services, etc) and map both performance and business priorities to those applications… such that when multiple applications are in contention for the same resource (disk, cache or CPU) the application with the highest priority gets dibs. When there is no contention, then all applications perform at peak performance. This enables Pillar’s customers to run Exchange, VMWare, File Services, and anything else they want on a single storage array and get deterministic performance on an application by application basis.

There is no better storage array than the Axiom. It wastes less, gives more performance, and delivers more value far more cost effectively than any solution from EMC or anyone else in the market. Watch Chuck ignore this one…he has to.