Tag Archive for SFD8

Violin Memory have cool technology, but do they have a future? I hope so!

Since visiting Violin Memory at Storage Field Day 8, it has taken me a while to get around to writing this post, and I guess the reason is because I am both frustrated, and a little bit sad.

They were the first guys who (for me at least) truly tamed the beast that is flash storage, packed it up into a blisteringly fast product with insanely low latencies, and released it into the big wide world.

An organisation I worked at took that product and threw thousands of desktop users at it, a number of very busy SQL TempDBs, and some other frankly evil workloads. It didn’t even blink an eye! With Violin Storage on the back, I have seen RDS desktop customers stress test the platform with up to 100 users in a single VM!

The thing that makes me sad is that to date, Violin have not yet turned a profit.

This is not some upstart company out of the boondocks! This is a mature company, founded in 2005, who provide their product to some of the biggest enterprises in the world. Yet so far they have not managed to make a penny!

Anyway, there are other guys in the industry who are far better at financial analysis than me (for example Justin Warren did a post on this very subject just last week). So I will leave it to them try to work out why this is the case, because I like to talk tech!

Violin Memory

Looking at the latest incarnation, once again Violin have “evolutionized” [sic] something which is technically very impressive.

  • The original Violin OS has been given the boot and has been replaced by something they call Concerto OS, which blends elements of the original software with some updated features. In development is also support for a multi-controller configuration beyond the current dual, though this is obviously not GA yet.
  • The new dual controller Flash Storage Platform supports FC, iSCSI and Infiniband, as well as RDMA and ROCE.
  • It is all packaged in a 3U appliance with up to 64 redundant flash modules.
  • Thanks to their own custom backplane design, it is capable of 10-12GB/sec of throughput!
  • At 100% sustained writes they have measured 400,000 IOPSat RAID5, which is more than many of their competitors can achieve with 100% reads!It should be noted that this was on the performance model, which does not support dedupe.

All in all the new solution just screams FAST! In fact, I’m surprised they didn’t paint a red stripe down the side of the chassis!

low latency

So why on earth are Violin not ruling the AFA world right now? As a frickin cool technology with hyper speed storage, they deserve to be up there at the very least!

If I had to hazard a guess, it’s because for most companies, good is good enough.

With the smorgasbord of All Flash Arrays available today, if you don’t need latency measured in microseconds and massive IOPS/bandwidth, then you have a huge array of choices (pardon the pun). At that point features, price and support become more important than straight line drag racer performance.

If Violin want to compete with the general market whilst servicing their high-speed clients, then they need to concentrate on continuing to developing a wider range of data services and providing entry-level options to consume their products. The last thing you want to do is lose business just because you were missing a check box in an RFP…

If Violin can stop burning cash and break even, then perhaps they have a future. I for one, hope so!

If you want to catch Violin’s presentation from SFD8, check them out here:
http://techfieldday.com/appearance/violin-memory-presents-at-storage-field-day-8/

They will also be presenting again at SFD9 this week, and I’m looking forward to finding out what they plan to do next!

Further Reading
Some of the other SFD8 delegates have their own takes on the presentation we saw. Check them out here:

Disclaimer/Disclosure: My flights, accommodation, meals, etc, at Storage Field Day 8 were provided by Tech Field Day, but there was no expectation or request for me to write about any of the vendors products or services and I was not compensated in any way for my time at the event.

Secondary can be just as important as Primary

There can be little doubt these days, that the future of the storage industry for primary transactional workloads is All Flash. Finito, that ship has sailed, the door is closed, the game is over, [Insert your preferred analogy here].

Now I can talk about the awesomeness of All Flash until the cows come home, but the truth is that flash is not now, and may never be as inexpensive for bulk storage as spinning rust! I say may as technologies like 3D NAND are changing the economics for flash systems. Either way, I think it will still be a long time before an 8TB flash device is cheaper than 8TB of spindle. This is especially true for storing content which does not easily dedupe or compress, such as the two key types of unstructured data which are exponentially driving global storage capacities through the roof year on year; images and video.

With that in mind, what do we do with all of our secondary data? It is still critical to our businesses from a durability and often availability standpoint, but it doesn’t usually have the same performance characteristics as primary storage. Typically it’s also the data which consumes the vast majority of our capacity!

AFA Backups

Accounting needs to hold onto at leat 7 years of their data, nobody in the world ever really deletes emails these days (whether you realise or not, your sysadmin is probably archiving all of yours in case you do something naughty, tut tut!), and woe betide you if you try to delete any of the old marketing content which has been filling up your arrays for years! A number of my customers are also seeing this data growing at exponential rates, often far exceeding business forecasts.

Looking at the secondary storage market from my personal perspective, I would probably break it down into a few broad groups of requirements:

  • Lower performance “primary” data
  • Dev/test data
  • Backup and archive data

As planning for capacity is becoming harder, and business needs are changing almost by the day, I am definitely leaning more towards scale-out solutions for all three of these use cases nowadays. Upfront costs are reduced and I have the ability to pay as I grow, whilst increasing performance linearly with capacity. To me, this is a key for any secondary storage platform.

One of the vendors we visited at SFD8, Cohesity, actually targets both of these workload types with their solution, and I believe they are a prime example of where the non-AFA part of the storage industry will move in the long term.

The company came out of stealth last summer and was founded by Mohit Aron, a rather clever chap with a background in distributed file systems. Part of the team who wrote the Google File System, he went on to co-found Nutanix as well, so his CV doesn’t read too bad at all!

Their scale-out solution utilises the now ubiquitous 2u, 4-node rack appliance physical model, with 96TB of HDDs and a quite reasonable 6TB of SSD, for which you can expect to pay an all-in price of about $80-100k after discount. It can all be managed via the console, or a REST API.

Cohesity CS2000 Series

2u or not 2u? That is the question…

That stuff is all a bit blah blah blah though of course! What really interested me is that Cohesity aim to make their platform infinitely and incrementally scalable; quite a bold vision and statement indeed! They do some very clever work around distributing data across their system, whilst achieving a shared-nothing architecture with a strongly consistent (as opposed to eventually consistent), 2-phase commit file system. Performance is achieved by first caching data on the SSD tier, then de-staging this sequentially to HDD.

I suspect the solution being infinitely scalable will be difficult to achieve, if only because you will almost certainly end up bottlenecking at the networking tier (cue boos and jeers from my wet string-loving colleagues). In reality most customers don’t need infinite as this just creates one massive fault domain. Perhaps a better aim would be to be able to scale massively, but cluster into large pods (perhaps by layer 2 domain) and be able to intelligently spread or replicate data across these fault domains for customers with extreme durability requirements?

Lastly they have a load of built-in data protection features in the initial release, including instant restore, and file level restore which is achieved by cracking open VMDKs for you and extracting the data you need. Mature features, such as SQL or Exchange object level integration, will come later.

Cohesity Architecture

Cohesity Architecture

As you might have guessed, Cohesity’s initial release appeared to be just that; an early release with a reasonable number of features on day one. Not yet the polished article, but plenty of potential! They have already begun to build on this with the second release of their OASIS software (Open Architecture for Scalable Intelligent Storage), and I am pleased to say that next week we get to go back and visit Cohesity at Storage Field Day 9 to discuss all of the new bells and whistles!

Watch this space! 🙂

To catch the presentations from Cohesity as SFD8, you can find them here:
http://techfieldday.com/companies/cohesity/

Further Reading
I would say that more than any other session at SFD8, the Cohesity session generated quite a bit of debate and interest among the guys. Check out some of their posts here:

Disclaimer/Disclosure: My flights, accommodation, meals, etc, at Storage Field Day 8 were provided by Tech Field Day, but there was no expectation or request for me to write about any of the vendors products or services and I was not compensated in any way for my time at the event.

Why are storage snapshots so painful?

Have you ever wondered why we don’t use snapshots more often than about every 5-15 minutes in most solutions, and in many others, a lot less often than that?

It’s pretty simple to be honest… The biggest problem with taking snapshots is quiescing the data stream to complete the activity. At a LUN level, this usually involves some form of locking mechanism to pause all IO while any metadata updates or data redirections are made, after which the IO is resumed.

For small machines and LUNs with minimal IO load this is generally such a quick operation that it has virtually no effect on the application user, and is pretty much transparent. For busy applications, however, data can be changing at such a massive rate that disrupting that IO stream, even for a few seconds can have a significant impact on performance and user experience. In addition the larger the number of snapshots in the snap tree, the more that performance is often degraded through the management of large numbers of snapshots, copy on write activities, and, of course, lots of locking.

This problem is then multiplied several times over when you want to get consistency across multiple machines, for example when you want to get point-in-time consistency for an entire application stack (Web / App / DB, etc).

So what do we typically do? We reduce the regularity at which we take these snaps in order to minimise the impact, whilst still having to meet the (usually near zero because all data is critical, right?) RPO set by the business.

At SFD8, we had a very well received presentation from INFINIDAT, a storage startup based in Israel and founded by industry legend Moshe Yanai (the guy who brought you EMC Symmetrix / VMAX, and subsequently XIV). Moshe’s “third generation” enterprise class storage system comes with one particular feature with which I was really interested; snapshots! Yes, I know it sounds like a boring “checkbox in an RFP” feature, but when I found out how it worked I was really impressed.

For every single write stripe which goes to disk, a checksum and a timestamp (from a high precision clock) are written. This forms the base on which the snapshot system is built (something they call InfiniSnap™).

If you have a micro-second accurate clock and timestamps on every write, then in order to achieve a snapshot you simply have to pick a date and time! Anything written earlier than this is not included in the current snap, and anything on or after the time is. This means no locking or pausing of IO during a snap, making the entire process a near zero time and a zero impact operation! A volume with or without snapshots, therefore has indistinguishable performance. Wow!

Screen Shot 2015-12-13 at 20.55.19

It sounds so simple it shouldn’t work, but according to INFINIDAT they can easily support up to 100,000 snaps per system, and even this isn’t even a real number. They made it up as it was a double figure percentage bigger than the next closest array on the market. They will also happily support more than this if you ask, they said that they just need to test it first. In addition, each snap group will support up to 25 snaps per second, and they guarantee an RPO of as low as 4 seconds, based on snapshots alone. You can then use point in time replication to create an asynchronous copy on another array if needed. Now that’s granular! 🙂

The one caveat I would add to this is that this does not yet appear to have a fix for ye old faithful crash consistent vs application consistent issue, but it’s a great start. Going back to the application stack “consistency group” concept, in theory, you generally only need to VSS the database VM, and as such it will be much easier and simpler to have a consistent snap across an app stack with minimal overhead. As we move more towards applications using No-SQL databases etc, this will also become less of an issue.

The above was just one of the cool features they covered in their presentation, from which the general consensus was very positive indeed! A couple of weeks ago I was also able to spend a little time with one of INFINIDAT’s customers who just so happened to be attending the same UKVMUG event. Their impressions in terms of the quality of the array build (with a claimed 99.99999% availability!), the management interface, general performance during initial testing, the compelling pricing, and of course, their very funky matrix-like chassis, were all very positive too.

If you want to see the INFINIDAT presentation from SFD8, make sure you have your thinking hat on and a large jug of coffee! Their very passionate CTO, Brian Carmody, was a very compelling speaker and was more than happy to get stuck into the detail of how the technology works. I definitely felt that I came away a little smarter having been a part of the audience! He also goes into some fascinating detail about genome sequencing, the concept of cost per genome and it’s likely massive impact on the storage industry and our lives in general! The video is worth a watch for this section alone…

Further Reading
Some of the other SFD8 delegates have their own takes on the presentation we saw. Check them out here:

Dan FrithINFINIDAT – What exactly is a “Moshe v3.0”?
Enrico Signoretti’s blog Juku.itInfinidat: awesome tech, great execution
Enrico Signoretti writing on El RegHas the next generation of monolithic storage arrived?
Ray LucchesiMobile devices as a cache for cloud data
Vipin V.K. – Infinibox – Enterprise storage solution from Infinidat
GreyBeards on Storage Podcast – Interview with Brian Carmody

Disclaimer/Disclosure: My flights, accommodation, meals, etc, at Storage Field Day 8 were provided by Tech Field Day, but there was no expectation or request for me to write about any of the vendors products or services and I was not compensated in any way for my time at the event.

Where and why is my data growing?…

I’ve written recently about issues of data gravity and data inertia, and about how important analytics are to managing your data “stockpile”, but one thing I haven’t gone into is the constant challenge of actually understanding your data composition, i.e. what the hell am I actually storing?!

Looking back to my days as a Windows admin maintaining what for the time were some massive, multi-terabyte (ooer – it was 10 years ago to be fair), filers and shared document storage systems; we had little to tell us what the DNA of those file shares was, how much of it was documents and other business-related content, and how much of it was actually people storing their entire MP3 collections and “family photos” on their work shared drives (yes, 100% true!).

Back then our only method of combating these issues was to run TreeSize to see who was using most space, then do windows searches for specific file types and manually clear out the crud; an unenviable task which came across a few surprising finds I won’t go into just now (ooer for the second time)! The problem was that we just didn’t know what we had!

Ten years later I have spoken to customers who are consuming data at very significant rates, but don’t have a grip on where it’s all going…

With that in mind, I was really interested in what the chaps at Qumulo had come up with when they presented at SFD8 recently. As they said at the time, the management of storage is getting easier, but the management of data is getting very much harder! Their primary vision is therefore quite succinctly described as “Build visible data and make storage invisible”.

Their “Data Aware” scale-out NAS solution is based around providing near-realtime analytics on the metadata, and was designed to meet the requirements of the 600 companies and individuals they interviewed before they even came up with their idea!

The product is designed to be software only and subscription-based, though they also provide scale out physical 1u / 4u appliances as well. I guess the main concept there is “have it your way”; there are still plenty of customers out there who want to buy software solution which is pre-qualified and supported on specific hardware (which sounds like an oxymoron but each to their own I say)! Most of Qumulo’s customers today actually buy the appliances.

The coolest thing about their solution is definitely their unique file system (QSFS – Qumulo Scalable File System). It uses a very clever, proprietary method to track changes within the filesystem based on the aggregate of child attributes in the tree (see their SFD8 presentation for more info). As you then don’t need to necessarily walk the entire tree to get an answer to a query (it should be noted this would be one specifically catered for by Qumulo though). It can then present statistics based on those attributes in near-realtime.

Whiteboard Dude approves!

Whiteboard Dude approves!

I would have killed for this level and speed of insight back in my admin days, and frankly I have a few customers right now who would really benefit!

Taking this a step further, the analytics can also provide performance statistics based on file path and type, so for example it could show you where the hotspots are in your filesystem, and which clients are generating them.

Who's using my storage?

Who’s using my storage?

Stuff I would like to see in future versions (though I know they don’t chase the Service Provider market), would be things like the ability to present storage to more than one Active Directory domain, straight forward RBAC (Role Based Access Control) at the management layer, more of the standard data services you see from most vendors (the RFP tick box features). Being able to mix and match the physical appliance types would also be useful as you scale and your requirements change over time, but I guess if you need flexibility, go with the software-only solution.

At a non-feature level, it would be sensible if they could rename their aggregate terminology as I think it just confuses people (aggregates typically mean something else to most storage bods).

Capacity Visualisation

Capacity Visualisation

Overall though I think the Qumulo system is impressive, as are the founder’s credentials. Their CEO/CTO team of Peter Godman and Aaron Passey, with whom we had a good chinwag outside of the SFD8 arena, both played a big part in building the Isilon storage system. As an organisation they already regularly work with customers with over 10 billion files today and up to 4PB of storage.

If their system is capable of handling this kind of scalability having only come out of stealth 8 months ago, they’re definitely one to watch…

Further Reading
Some of the other SFD8 delegates have their own takes on the presentation we saw. Check them out here:

Dan Frith – Qumulo – Storage for people who care about their data

Scott D. Lowe – Data Awareness Is Increasingly Popular in the Storage Biz

Disclaimer/Disclosure: My flights, accommodation, meals, etc, at Storage Field Day 8 were provided by Tech Field Day, but there was no expectation or request for me to write about any of the vendors products or services and I was not compensated in any way for my time at the event.

 

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