By Editor
Flash continues to gain traction throughout the storage landscape as the technology removes several bottlenecks of I/O performance
Flash storage in the enterprise segment is gaining ground for very obvious reasons. Reduced costs of Flash memory are making it conceivable to have more data stored on Flash arrays. Several bottlenecks in traditional enterprise data center storage have caused an acceleration towards flash storage arrays as a general trend in data centers globally. Leading vendors including EMC, Hitachi, IBM and so on have added flash drives to their existing arrays.
With application performance and availability top priority for Businesses, Flash helps deliver reduced data processing times and faster application service uptime. Keeping more active content on SSD arrays helps retrieve and deliver that data much faster. This is more in the case of critical applications that need high IOPS (Input /Output Operations Per Second) storage performance. Virtualization and demands of cloud computing are further accentuating the need for Flash storage arrays in enterprise data centers.
According to Pure Storage, a vendor focused on enterprise storage Technologies, there are similar trends in all regions of its business including MEA and therefore a growing demand for Flash arrays. The company’s distributor in the region, Global Distribution FZE has already commenced Partner recruitment and enablement, both Technical and Sales.
Steven Rose VP EMEA Pure Storage says, “In the virtualized datacenter, it is now commonly I/O performance that limits server consolidation ratios, not CPU or memory. These bottlenecks can affect customer satisfaction and slow down business processes. Further, Virtualization has the effect of multiplexing multiple logical workloads across a single physical I/O path. The greater the consolidation achieved through virtualization, the more randomized the physical I/O requests become. And random I/O is the Achilles heel of the rotational disk drive, because seek and rotational latency dominate transfer times 20 to 1.”
While Virtualization randomizes I/O as a variety of IO workloads are run together against the storage stack, the legacy storage based on traditional HDDs is mostly designed for sequential I/O. When a multitude of applications and services are competing against the resources of a spinning disk storage array the response times gets higher and higher and the disk array struggles to keep up as result of bottlenecks caused by the disk contention.
Christian Putz, Vice President-EMEA Channel Sales at Violin Memory, a leading provider of all-flash storage arrays and appliances delivering application solutions for the enterprise says, “Flash technology allows to run random workloads without having backend contention, and specifically speaking, the Violin Memory Flash technology provides sustained, predictable and sub-milisecond latencies for any kind of random workload (even with a huge component of writes). With Violin Memory Flash technology running mixed workloads results in no I/O penalty and allows to fully virtualize business critical applications, sustain high performance for all virtualized databases and applications and fully adopt VDI deployments because of an increased VDIs/core ratio. Last but not least, Violin Memory Flash technology dramatically reduces the impact of overcommitting resources, which typically occurs in this space, and allows to even run more VMs per host with low latency storage.”
According to Steven, while the demand for IOPS is growing, the supply is actually shrinking because the I/O rate to a single hard drive has been roughly constant while the capacity of a hard drive doubles every 18 months or so. This means that their performance per GB is actually declining. Therefore Flash is poised to have a disruptive effect on the enterprise storage market by applying solid state storage to tier 1 applications in the data center.
He adds, “A solid state storage solution based on flash removes these bottlenecks because it has no seek time, no rotational latency, and is equally fast on random workloads as on sequential ones, he says. Flash can accelerate virtual server and desktop deployments while affording higher consolidation and greater efficiency. Flash can also accelerate SQL and NoSQL workloads without partitioning or changes to the application. With flash memory, any block of data can be fetched in nearly constant time. This means that applications can be designed to expect sub-millisecond latency no matter what the I/O stream (random or sequential) or data distribution. Also, Solid state storage uses 10x less power and space than rotational hard drives, allowing you to substantially expand capacity in place. Further, with all flash arrays, customers spend much less time planning and tuning their arrays to remove bottlenecks.”
Flash all the way
Vendors are delivering hybrid arrays that include Flash and hard drives as well as all flash arrays which contain multiple flash memory drives instead of hard disk drives. Industry experts suggest that deployments must take into account use case scenarios. For instance, typical application workloads will see a considerable improvement in performance as well as savings in power, cooling etc with marginal inclusion of flash technology. Therefore, the hybrid approach works out as a viable option to accelerate workload performance. However, there are also application scenarios that demand dramatic improvements in response-time performance (latency) or high IOPS which are well taken care of all Flash array options.
All-flash arrays have been designed from the ground up to work with flash media unlike traditional arrays that have been built to work with the relatively slower spinning hard drives.
Christian says, “All Flash is one of the fastest growing markets in IT infrastructure. Nowadays, real-time data access and operational efficiency are the new norms and IT forces are starting to drive a transformation of the datacenter pushed by the demands of Business Critical Applications, full Enterprise Virtualization adoption, Data analytics, etc. “
He adds, “As Flash storage is a proven and mature technology and we are seeing Tier 1 apps and virtualization driving adoption of flash arrays. VDI, Transactional databases, Data analytics, ERPs, and Cloud initiatives are being moved towards an All-Flash storage to make real-time data access and operational efficiency become a reality: a tremendous boost in performance with dramatically reduced response times allows not only guaranteeing the future business growth pace, but it also provides higher consolidation ratios, to be able to fully embrace business critical application virtualisation, to reduce over-provisioning, to reduce licensing costs by increasing compute node utilization, and an impressive datacenter footprint reduction.”
A great example of the impact of Flash instead of legacy hard disk drives is in a Virtual Desktop environment. According to Pure Storage, one of the biggest challenges VDI presents to storage is the variable and spikey nature of IO requirements throughout the day. Typical use is write-heavy (often 80/20), but boot storms and anti-virus scans introduce huge read spikes. Overnight maintenance tasks (patches, recomposes) introduce even more heavy write bursts. You need storage that keeps up with it all without sacrificing end-user experience the way a caching solution can. This is another great example of where flash really outpaces hard disk drive based hybrid arrays.
Steven elaborates, “Many VDI pilots go well– until it is time to scale-up the deployment and move into production. That’s where too often deployments hit the IO wall – exceeding the IO capabilities of traditional disk storage and requiring expensive additional storage purchases which blow the VDI ROI case. Pure Storage scales seamlessly from pilot of a few hundred to 1,000s of users, all with non-disruptive incremental capacity and resiliency expansion. If all the benefits of VDI (security, consolidation for managent, etc.) can meet or exceed the performance of local laptop performance, then more and more customers will consider to move to Virtual Desktop.”
Salil Dighe, the CEO at Meta Byte Technologies, a regional partner for FusionIO, that was recently acquired by SanDisk claims that the region has been slow and cautious in its adoption of Flash storage as they haven’t seen significant gains from traditional Flash storage options available from different vendors.
He says, “The Middle East region is a followers market. The other parts of the world have already tried to utilize flash storage arrays and have not seen much benefit in terms of performance increase or IOPS. For the investments vs performance the gains are minimal hence now they are turning towards what is known as Flash on PCIe. One such product is FusionIO which seems to turn heads and provides significant throughput in terms of IOPS. Today many of the customers prefer FusionIO due to its flexibility in supporting various scenarios be it increasing the IOPS on a standard tier1 server to server virtualization or to provide significantly high VDI and VM densities on the same servers.“
PCIe (Peripheral Component Interconnect Express) based solid-state storage has better performance than server-based SATA, SAS or Fibre Channel (FC) solid-state drives because of the direct connections.
He adds, “If you are using a disk controller to write on hard drives whether flash or non-flash the bottle neck is still the controller. The difference can only be significant if you use Flash as a memory tier. FusionIO uses Flash memory in its best suited architecture that is flash on PCIe, meaning CPU has faster access to data. As a result the CPU is efficiently utilized and can process many more operations or support more connections.”
The transition in effect
The transition from to flash arrays is bound to accelerate. This would suit the growing virtualized environments as Flash helps customers eliminate bottlenecks of applications delivery in virtual environments. So will hard disk drives have a place in the data centres in the long term?
Responding to that question, Steven says, “In some areas such as deep archive, or areas where performance isn’t a requirement, then hard disks may be here to stay for some period of time. But with the pace of innovation and focus on the flash industry, its anyone’s guess as to how soon even large footprint slow hard disk drives might be replaced by SSD(solid state drives). Consider that in early 2014 the standard Enterprise All flash array SSD was 512GB and by the beginning of 2015 this could be 2TB per SSD and you can see why we could be rid of hard disk drives much faster than most Enterprises anticipate. Therefore we recommend highly that all customers when making their storage refresh plans consider the benefits of an All-flash approach to storage.”
Combining the speed of flash SSDs with the capacity of HDDs has enabled faster access to hot data, while keeping cold data that is not critically needed on high-capacity HDDs. The Flash manufacturers are emphatic that the trend is bound to accelerate.
“We clearly see flash memory as the Tier-1 storage for the enterprise datacenter, as it needs to be offer the highest sustained performance with the lowest possible latency while keeping the lowest cost per I/O. And this is actually starting to be a reality for Violin Memory customers. Traditional hard disk based storage will be still the preferred solution for reference data as it needs to be capacity optimised and needs to offer the lowest possible cost per GB (at the expense of inducing a high cost per I/O),” says Christian.
According to him, the cost benefits of Traditional disk based storage needs to be relooked as traditional disk storage offers the best possible cost per GB but the worst $/Transaction ratio compared to Flash. So price and cost is still a concern when all the variables are not properly set into the equation.
He adds, “Nevertheless, Flash storage is evolving very fast and the fact is that Violin Memory´s technology is even exceeding Moore´s law: flash density and performance is doubling every ~16 months.
Violin Memory´s unique intellectual property is leading the market by continuously developing the next generation of flash technology. This will guarantee continuing the same pace of doubling or even quadrupling the capacity and performance, and when combined with additional data efficiency mechanisms like compression and de-duplication this results in many PBs of Flash with dozens of millions of IOPS per Rack with a lower CAPEX/GB than performance disk. “
According to Dighe, Cost is definitely a big concern and a bottleneck. In order to take advantage of Flash in the most limited budgets, enterprises must look at different architectures and not go by legacy storage providers. They should consider hybrid storage which allows enterprises to take benefit of both Flash as well as HDD’s and can outperform any standard flash enabled enterprise storage in a single appliance.
He says, “Definitely we see customers replacing hard disk and standard enterprise storage with flash technology provided they are able to deliver high performance in a small hardware infrastructure footprint. For example, FusionIO has proved recently that they can achieve 1.1 Billion IOPS using 8 standard tier one servers with one FusionIO drives in each server leading to a quantum leap in terms performance and acceleration, which has never seen before.”
Pure Storage claims that a number of customers that have completely eliminated their legacy hybrid hard disk drive-based arrays in exchange for All Flash Arrays.
“We continue to engage with the thought leaders in many of our Enterprise customers that are seeking advice in terms of planning to eliminate hard disk from their data centres because of the many benefits of All flash storage arrays. Thanks to data reduction techniques such as compression and deduplication implemented by Pure Storage, flash has already become the preferred choice of business critical applications, and that trend is increasing. Nearly 50% of all flash storage for Pure Storage is made up of database applications because of the ability to get data reduction 3-10X. “
So there it is. Flash enabled datacenters are likely to be one of the major shifts on the IT Infrastructural roadmap.