No Flash in the pan

The storage networking market now is teeming with flash solutions. Consumers are probably sick to their stomach getting a better insight which flash solution they should be considering. There are so much hype, fuzz and buzz and like a swarm of bees, in the chaos of the moment, there is actually a calm and discerning pattern slowly, but surely, emerging. Storage networking guys would probably know this thing well, but for the benefit of the other readers, how we view flash (and other solid state storage) becomes clear with the picture below: Flash performance gap

(picture courtesy of  http://electronicdesign.com/memory/evolution-solid-state-storage-enterprise-servers)

Right at the top, we have the CPU/Memory complex (labelled as Processor). Our applications, albeit bytes and pieces of them, run in this CPU/Memory complex.

Therefore, we can see Pattern #1 showing up. (more…)

Correcting NCQ incorrect portrayal with SSDs

A kind reader, Baruch Even, has pointed out my ignorance with SATA Native Command Queuing (NCQ) working with Solid State Drives (SSDs) in my previous blog.

In the post, I have haphazardly stated that NCQ was meant for spinning mechanical drives. I was wrong.

NCQ does indeed improve the performance of SSDs using SATA interfaces, and sometimes as much as 15-20%. I know there is a statement in the SATA Wikipedia page that says that NCQ boosted IOPS by 100% but I would take a much more realistic view of things rather than setting the expectations too high.

The typical SSD consists of flash storage spread across multiple chips, which in turn are a bunch of flash packages. Within each of the flash packages, there are different dies (as in manufacturing terminology “die”, not related to the word of “death”) that houses planes (not related to aeroplanes) and subsequently into blocks and pages.

(more…)

The big boys better be flash friendly

An interesting article came up in the news this week. The article, from the ever popular The Register, mentioned 3 up and rising storage stars, Nimble Storage, Tintri and Tegile, and their assault on a flash strategy “blind spot” of the big boys, notably EMC and NetApp.

I have known about Nimble Storage and Tintri for a couple of years now, and I did take some time to read up on their storage technology offering. Tegile is new to me when it appeared on my radar after SearchStorage.com announced as the Gold Winner of the enterprise storage category for 2012.

The Register article intriqued me because it implied that these traditional storage vendors such as EMC and NetApp are probably doing a “band-aid” when putting together their flash storage strategy. And typically, I see these strategic concepts introduced by these 2 vendors:

  1. Have a server-side cache strategy by putting a PCIe card on the hosting server
  2. Have a network-based all-flash caching area
  3. Have a PCIe-based flash card on the storage system
  4. Have solid state drives (SSDs) in its disk shelves enclosures

In (1), EMC has VFCache (the server side caching software has been renamed to XtremSW Cache and under repackaging with the Xtrem brand name) and NetApp has it FlashAccel solution. Previously, as I was informed, FlashAccel was using the FusionIO ioTurbine solution but just days ago, NetApp expanded the LSI Nytro WarpDrive into its FlashAccel solution as well. The main objective of a server-side caching strategy using flash is to accelerate mostly read-based I/O operations for specific application workloads at the server side.

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Say VDI very fast

This one bugs me.

All the talk about Virtual Desktop Infrastructure (VDI) and how VDI is the next IN thing is beginning to look like hulla baloo to me. Every storage vendor in town is packaging their VDI messaging in the best gift wrapping paper possible, trying to win the hearts of potential customers. But I have a creeping feeling that the customers in Malaysia and even perhaps some in the region are going to be disappointed when all the fluff and huff of VDI meets reality.

I have to admit that I have no experience with VDI. I have no implementation experience, and I have no selling experience of VDI, but having gone through the years looking and observing at the centralized computing and thin client space, history could be repeating itself (again!). Many previous pre-VDI experiences have fallen flat on the face.

Remember the days of X-terminals, early versions of thin clients? Remember the names such as NCD (Network Computing Devices), Wyse Technologies (they were recently acquired by Dell), SCO Tarantella and the infamous Javastation? I don’t know about you, but that Javastation design was one ugly motherf****r.

So, it is my pleasure to remind you again and hopefully give you some nightmares too ;-)

Back to VDI. Yes, the thin-client/zero-client/remote desktop/VDI concept is a great idea! I would have love VDI to be successful. It will be the implementation and the continuous user complaints that will be the bane of its problems. Ultimately, it’s the user’s experience that counts. (more…)

ARC reactor also caches?

The fictional arc reactor in Iron Man’s suit was the epitome of coolness for us geeks. In the latest edition of Oracle Magazine, Iron Man is on the cover, as well as the other 5 Avengers in a limited edition series (see below).

Just about the same time, I am reading up on the ARC (Adaptive Replacement Caching) that is adopted in ZFS. I am learning in depth of how ZFS caching works as opposed to the more popular LRU (Least Recently Used) caching algorithm that is used in most storage cache memory. Having said that, most storage vendors employed a modified LRU algorithm, with the intention to keep the most recently accessed pages in memory as long as possible. This is true in NetApp’s Data ONTAP (maybe not the ONTAP GX in which I have little experience) and EMC FlareOE. ONTAP goes further to by keeping the most frequently accessed pages permanently in memory. EMC folks would probably refer to most recently accessed as spatial locality while most frequently accessed as temporal locality.

Why is ZFS using ARC and what is ARC? (more…)

Server way of locked-in storage

It is kind of interesting when every vendor out there claims that they are as open as they can be but the very reality is, the competitive nature of the game is really forcing storage vendors to speak open, but their actions are certainly not.

Confused? I am beginning to see a trend … a trend that is forcing customers to be locked-in with a certain storage vendor. I am beginning to feel that customers are given lesser choices, especially when the brand of the server they select for their applications  will have implications on the brand of storage they will be locked in into.

And surprise, surprise, SSDs are the pawns of this new cloak-and-dagger game. How? Well, I have been observing this for quite a while now, and when HP announced their SMART portfolio for their storage, it’s time for me to say something.

In the announcement, it was reported that HP is coming out with its 8th generation ProLiant servers. As quoted:

The eighth generation ProLiant is turbo-charging its storage with a Smart Array containing solid state drives and Smart Caching.

It also includes two Smart storage items: the Smart Array controllers and Smart Caching, which both feature solid state storage to solve the disk I/O bottleneck problem, as well as Smart Data Services software to use this hardware

From the outside, analysts are claiming this is a reaction to the recent EMC VFCache product. (I blogged about it here) and HP was there to put the EMC VFcache solution as a first generation product, lacking the smarts (pun intended) of what the HP products have to offer. You can read about its performance prowess in the HP Connect blog.

Similarly, Dell announced their ExpressFlash solution that ties up its 12th generation PowerEdge servers with their flagship (what else), Dell Compellent storage.

The idea is very obvious. Put in a PCIe-based flash caching card in the server, and use a condescending caching/tiering technology that ties the server to a certain brand of storage. Only with this card, that (incidentally) works only with this brand of servers, will you, Mr. Customer, be able to take advantage of the performance power of this brand of storage. Does that sound open to you?

HP is doing it with its ProLiant servers; Dell is doing it with its ExpressFlash; EMC’s VFCache, while not advocating any brand of servers, is doing it because VFCache works only with EMC storage. We have seen Oracle doing it with Oracle ExaData. Oracle Enterprise database works best with Oracle’s own storage and the intelligence is in its SmartScan layer, a proprietary technology that works exclusively with the storage layer in the Exadata. Hitachi Japan, with its Hitachi servers (yes, Hitachi servers that we rarely see in Malaysia), already has such a technology since the last 2 years. I wouldn’t be surprised that IBM and Fujitsu already have something in store (or probably I missed the announcement).

NetApp has been slow in the game, but we hope to see them coming out with their own server-based caching products soon. More pure play storage are already singing the tune of SSDs (though not necessarily server-based).

The trend is obviously too, because the messaging is almost always about storage performance.

Yes, I totally agree that storage (any storage) has a performance bottleneck, especially when it comes to IOPS, response time and throughput. And every storage vendor is claiming SSDs, in one form or another, is the knight in shining armour, ready to rid the world of lousy storage performance. Well, SSDs are not the panacea of storage performance headaches because while they solve some performance issues, they introduce new ones somewhere else.

But it is becoming an excuse to introduce storage vendor lock-in, and how has the customers responded this new “concept”? Things are fairly new right now, but I would always advise customers to find out and ask questions.

Cloud storage for no vendor lock-in? Going to the cloud also has cloud service provider lock-in as well, but that’s another story.

 

Lightning about to strike

Watch out for February 6th, 2012 folks! The Lightning is about to strike!

Yes, it is likely that EMC will be announcing their server-based, 8-lane PCIe Flash memory card in early week of February. The PCIe card was dubbed “Project Lightning” when it was first announced in EMC World in May last year. It represents EMC’s first foray of products that sits on the server side, giving the impression that EMC could be entering the server business. I blogged about this way back in September last year. As explained by the EMC folks, they are not going into the server business but rather “extending” their performance tiering into the server space. Think of it like an umbilical cord that  sucks the server’s CPU processing power to give maximum performance boost for the EMC storage.

The card will sport Solid State Drive from LSI Warp Drive and comes in 100/200/300GB capacity. Here’s a picture of how the Lightning card would look like:

The SSD is an SLC (Single Level Cell) and is capable of delivering 150,000 random reads IOPS based on 4K blocks and 190,000 random writes IOPS. It can squeeze 1.4GB/sec in read throughput. While it is not on par with the performance of Fusion-IO, it can definitely do well leveraging EMC’s huge customer base. Furthermore, PCIe-based Flash memory cards such as Fusion-IO will not be able to take advantage of the bridge that links the server and the storage, making it confined to the server’s resources. The advantage is definitely EMC when you explore the possibilities.

Here’s a view of a slide from Virtual Geek summarizing the Project Lightning:

The Lightning card is aimed at customers who demand the highest performance, even higher that Tier 0. It will be integrated with EMC’s FAST (Fully Automated Storage Tiering) technology and is available to the VNX and VMAX platforms.

So watch out folks, because Lightning is about to strike soon!

Is there IOPS for Cloud Storage? – Nasuni style

I was in Singapore last week attending the Cloud Infrastructure Services course.

In the class, one of the foundation components of Cloud Computing is of course, storage. As the students and the instructor talked about Storage, one very interesting argument surfaced. It revolved around the storage, if it was offered on the cloud. A lot of people assumed that Cloud Storage would be for their databases, and their virtual machines, which of course, is true when the communication between the applications, virtual machines and databases are in the local area network of the Cloud Service Provider (CSP).

However, if the storage is offered through the cloud to applications that are sitting on-premise in the customer’s server room, then we have to think twice of how we perceive Cloud Storage. In this aspect, the Cloud Storage offered by the CSP is a Infrastructure-as-a-Service (IaaS), where the key service is Storage. We have to differentiate that this Storage functions as a data container, and usually not for I/O performance reasons.

Though this concept probably will be easily understood by storage professionals like us, this can cause a bit confusion for someone new to the concept of Cloud Computing and Cloud Storage. This confusion, unfortunately, is caused by many of us who are vendors or solution providers, or even publications and magazines. We are responsible to disseminate correct information to customers, but due to our lack of knowledge and experience in this extremely new market of Cloud Storage, we have created the FUDs (Fear, Uncertainty and Doubt) and hype.

Therefore, it is the duty of this blogger to clear the vapourware, and hopefully pass on the right information to accelerate  the adoption of Cloud Storage in the near future. At this moment, given the various factors such as network costs, high network latency and lack of key network technologies similar to LAN in Cloud Computing, Cloud Storage is, most of the time, for data storage containership and archiving only. And there are no IOPS or any performance related statistics related to Cloud Storage. If any engineer or vendor tells you that they have the fastest Cloud Storage in the industry, do me a favour. Give him/her a knock on the head for me!

Of course, as technologies evolve, this could change in the near future. For now, Cloud Storage is a container, NOT a high performance storage in the cloud. It is usually not meant for transactional data. There are many vendors in the Cloud Storage space from real CSPs to storage companies offering re-packaged storage boxes that are “cloud-ready”. A good example of a CSP offering Cloud Storage is Amazon S3 (Simple Storage Service). And storage vendors such as EMC and HDS are repackaging and rebranding their storage technologies as object storage, ready for the cloud. EMC Atmos is really a repackaged and rebranded Centera, with some slight modifications, while HDS , using their Archiving solution, has HCP (aka HCAP). There’s nothing wrong with what EMC and HDS have done, but before the overhyping of the world of Cloud Computing, these platforms were meant for immutable data archiving reasons. Just thought you should know.

One particular company that captured my imagination and addresses the storage performance portion is Nasuni. Of course, they are quite inventive with the Cloud Storage Gateway approach. Nasuni comes up with a Cloud Storage Gateway filer appliance, which can be either a physical 1U server or as a VMware or Hyper-V virtual appliance sitting on-premise at the customer’s site.

The key to this is “on-premise”, which allows access to data much faster because they are locally-cached in the Nasuni filer appliance itself. This Nasuni filer piece addresses the Cloud Storage “performance” piece but Nasuni do not claim any performance statistics with such implementation. The clever bit is that this addresses data or files that are transactional in nature, i.e. NFS or CIFS, to serve data or files “locally”. (I wonder if Nasuni filer has iSCSI as well. Hmmmm….)

In the Nasuni architecture, they “break up” their “Cloud Storage” into 2 pieces. Piece #1 sits on-premise, at the customer site, and acts as a bridge to the Piece #2, that is sitting in a Cloud Storage. From a simplified view, have a look at the diagram below:

 

 

Piece #1 is the component that handles some of the transactional traffic related to files. In a more technical diagram below, you can see that the Nasuni filer addresses the file sharing portion, using the local disks on the filer appliance as a local caching mechanism.

 

Furthermore, older file pieces are whiffed away to the any Cloud Storage using the Cloud Connector interface, hence giving the customer a sense that their storage capacity needs can be limitless if they want to (for a fee, of course). At the same time, the Nasuni filer support thin provisioning and snapshots. How cool is that!

The Cloud Storage piece (Piece #2) is used for the data container and archiving reasons. This component can be sitting and hosted at Amazon S3, Microsoft Azure, Rackspace Cloud Files, Nirvanix Storage Delivery Network and Iron Mountain Archive Services Platform.

The data communication and transfer between the Nasuni filer is secure, encrypted, deduplication and compressed, giving it the efficiency and security that most customers would be concerned about. The diagram below explains the dat communication and data transfer bit.

 

In this manner, the Nasuni filer can replace traditional NAS platforms and can potentially provide a much lower total cost of ownership (TCO) in the long run. Nasuni does not pretend to be a NAS replacement. To me, this concept is very inventive and could potentially change the way we perceive file sharing and file server, obscuring and blurring concept of NAS.

Again, I would like to reiterate that Nasuni does not attempt to say their solution is a NAS or a performance-based Cloud Storage but what they have cleverly packaged seems to be appealing to customers. Their customer base has grown 78% in Q2 of 2011. It’s just too bad they are not here in Malaysia or this part of the world (yet).

IOPS in Cloud Storage? Not yet.

 

Signs of things to come?

I wanted to sign off early tonight but an article in ComputerWorld caught my tired eyes. It was titled “EMC to put hardware into servers, VMs into storage” and after I read it, I couldn’t help but to juxtapose the articles with what I said earlier in my blogs, here and here.

It is very interesting to note that “EMC runs vSphere directly on the storage controllers and then uses vMotion to migrate VMs from application servers onto the storage array, ..” since the storage boxes have enough compute power to run Virtual Machines on the storage. Traditionally and widely accepted, VMs should be running on servers. Contrary to beliefs, EMC has already demonstrated this running of VMs capability on their VNX, Isilon and Symmetrix.

And soon, with EMC’s Project Lightning (announced at EMC World in May 2011), they will be introducing server side PCIe-based SSDs, ala Fusion-IO. This is different from the NetApp PAM/FlashCache PCIe-based card, which sits on their arrays, not on hosts or servers. And it is also very interesting to note that this EMC server-side PCIe Flash SSD card will become a bridge to EMC’s FAST (Fully Automated Storage Tiering) architecture, enabling it to place hot, warm and cold data strategically on different storage tiers of the applications on VMware’s VMs (now on either the server or the storage),  perhaps using vMotion as a data mover on top of the “specialized” link created by the server-side EMC PCIe card.

This also blurs the line between the servers and storage and creates a virtual architecture between servers and storage, because what used to be distinct data border of the servers is now being melded into the EMC storage array, virtually.

2 red alerts are flagging in my brain right now.

  1. The “bridge” has just linked the server back to the storage, after years of talking about networked storage. The server is ONE again with the storage. Doesn’t that look to you like a server with plenty of storage? It has come a full cycle. But more interesting and what I am eager to see is what more is this “bridge” capable of when it comes to data management. vMotion might be the first of many new “protocol” breeds to enhance data management and mobility with this “bridge”. I am salivating right now of this massive potential.
  2. What else can EMC do with the VMware API? This capability I am writing right now is made possible by EMC tweaking VMware’s API to maximize much, much more. As the VMware vStorage API is continually being enhanced, the potential is again, very massive and could change the entire landscape of cloud computing and subsequently, the entire IT landscape. This is another Pavlov’s dog moment (see figures below as part of my satirical joke on myself)

 

Sorry, the diagram below is not related to what my blog entry is. Just my way of describing myself right now. ;-)

I am extremely impressed with what EMC is doing. A lot of smarts and thinking go into this and this is definitely signs of things to come. The server and the storage are “merging again”. Think of it as Borg assimilation in Star Trek.

Resistance is futile!

Does all SSDs make sense?

I have been receiving a lot of email updates from Texas Memory Systems for many months now. I am a subscriber to their updates and Texas Memory System is the grand daddy of flash and DRAM-based storage systems. They are not cheap but they are blazingly fast.

Lately, more and more vendors have been coming out with all SSDs storage arrays. Startups such Pure Storage, Violin Memory and Nimbus Data Systems have been pushing the envelope selling all SSDs storage arrays. A few days ago, EMC also announced their all SSDs storage array. As quoted, the new EMC VNX5500-F utilizes 2.5-in, single-level cell (SLC) NAND flash drives to 10 times the performance of the hard-drive based VNX arrays. And that is important because EMC has just become one of the earliest big gorillas to jump into the band wagon.

But does it make sense? Can one justify to invest in an all SSDs storage array?

At this point, especially in this part of the world, I predict that not many IT managers are willing to put their head on the chopping board and invest in an all SSDs storage array. They would become guinea pigs for a very expensive exercise and the state of the economy is not helping. Therefore the automatic storage tiering (AST) might stick better than having an all SSDs storage array. The cautious and prudent approach is less risky as I have mentioned in a past blog.

I wrote about Pure Storage in a previous blog and the notion that SSDs will offer plenty of IOPS and throughput. If the performance gain translates into higher productivity and getting the job done quicker, then I am all for SSDs. In fact, given the extra performance numbers

There is no denying that the fact that the industry is moving towards SSDs and it makes sense. That day will come in the near future but not now for customers in these part of the world.