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I was asked some interesting questions recently by CEO & CIO, a Chinese business magazine. The questions ranged from how Chinese Internet giants like Alibaba, Baidu and Tencent differ from other customers and what leading technologies big Internet companies have created to questions about emerging technologies such as software-defined storage (SDS) and software-defined datacenters (SDDC) and changes in the ecosystem of datacenter hardware, software and service providers. These were great questions. Sometimes you need the press or someone outside the industry to ask a question that makes you step back and think about what’s going on.

I thought you might interested, so this blog, the first of a 3-part series covering the interview, shares details of the first two questions.

CEO & CIO: In recent years, Internet companies have built ultra large-scale datacenters. Compared with traditional enterprises, they also take the lead in developing datacenter technology. From an industry perspective, what are the three leading technologies of ultra large-scale Internet data centers in your opinion? Please describe them.

There are so many innovations and important contributions to the industry from these hyperscale datacenters in hardware, software and mechanical engineering. To choose three is difficult. While I would prefer to choose hardware innovations as their big ones, I would suggest the following as they have changed our world and our industry and are changing our hardware and businesses:

Autonomous behavior and orchestration
An architect at Microsoft once told me, “If we had to hire admins for our datacenter in a normal enterprise way, we would hire all the IT admins in the world, and still not have enough.” There are now around 1 million servers in Microsoft datacenters. Hyperscale datacenters have had to develop autonomous, self-managing, sometimes self-deploying datacenter infrastructure simply to expand. They are pioneering datacenter technology for scale – innovating, learning by trial and error, and evolving their practices to drive more work/$. Their practices are specialized but beginning to be emulated by the broader IT industry. OpenStack is the best example of how that specialized knowledge and capability is being packaged and deployed broadly in the industry. At LSI, we’re working with both hyperscale and orchestration solutions to make better autonomous infrastructure.

High availability at datacenter level vs. machine level
As systems get bigger they have more components, more modes of failure and they get more complex and expensive to maintain reliability. As storage is used more, and more aggressively, drives tend to fail. They are simply being used more. And yet there is continued pressure to reduce costs and complexity. By the time hyperscale datacenters had evolved to massive scale – 100’s of thousands of servers in multiple datacenters – they had created solutions for absolute reliability, even as individual systems got less expensive, less complex and much less reliable. This is what has enabled the very low cost structures of the cloud, and made it a reliable resource.

These solutions are well timed too, as more enterprise organizations need to maintain on-premises data across multiple datacenters with absolute reliability. The traditional view that a single server requires 99.999% reliability is giving way to a more pragmatic view of maintaining high reliability at the macro level – across the entire datacenter. This approach accepts the failure of individual systems and components even as it maintains data center level reliability. Of course – there are currently operational issues with this approach. LSI has been working with hyperscale datacenters and OEMs to engineer improved operational efficiency and resilience, and minimized impact of individual component failure, while still relying on the datacenter high-availability (HA) layer for reliability.

Big data
It’s such an overused term. It’s difficult to believe the term barely existed a few years ago. The gift of Hadoop® to the industry – an open source attempt to copy Google® MapReduce and Google File System – has truly changed our world unbelievably quickly. Today, Hadoop and the other big data applications enable search, analytics, advertising, peta-scale reliable file systems, genomics research and more – even services like Apple® Siri run on Hadoop. Big data has changed the concept of analytics from statistical sampling to analysis of all data. And it has already enabled breakthroughs and changes in research, where relationships and patterns are looked for empirically, rather than based on theories.

Overall, I think big data has been one of the most transformational technologies this century. Big data has changed the focus from compute to storage as the primary enabler in the datacenter. Our embedded hard disk controllers, SAS (Serial Attached SCSI) host bus adaptors and RAID controllers have been at the heart of this evolution. The next evolutionary step in big data is the broad adoption of graph analysis, which integrates the relationship of data, not just the data itself.

CEO & CIO: Due to cloud computing, mobile connectivity and big data, the traditional IT ecosystem or industrial chain is changing. What are the three most important changes in LSI’s current cooperation with the ecosystem chain? How does LSI see the changes in the various links of the traditional ecosystem chain? What new links are worth attention? Please give some examples.

Cloud computing and the explosion of data driven by mobile devices and media has and continues to change our industry and ecosystem contributors dramatically. It’s true the enterprise market (customers, OEMs, technology, applications and use cases) has been pretty stable for 10-20 years, but as cloud computing has become a significant portion of the server market, it has increasingly affected ecosystem suppliers like LSI.

Timing: It’s no longer enough to follow Intel’s ticktock product roadmap. Development cycles for datacenter solutions used to be 3 to 5 years. But these cycles are becoming shorter. Now, demand for solutions is closer to 6 months – forcing hardware vendors to plan and execute to far tighter development cycles. Hyperscale datacenters also need to be able to expand resources very quickly, as customer demand dictates.  As a result they incorporate new architectures, solutions and specifications out of cycle with the traditional Intel roadmap changes. This has also disrupted the ecosystem.

End customers: Hyperscale datacenters now have purchasing power in the ecosystem, with single purchase orders sometimes amounting to 5% of the server market.  While OEMs still are incredibly important, they are not driving large-scale deployments or innovating and evolving nearly as fast. The result is more hyperscale design-win opportunities for component or sub-system vendors if they offer something unique or a real solution to an important problem. This also may shift profit pools away from OEMs to strong, nimble technology solution innovators. It also has the potential to reduce overall profit pools for the whole ecosystem, which is a potential threat to innovation speed and re-investment.

New players: Traditionally, a few OEMs and ISVs globally have owned most of the datacenter market. However, the supply chain of the hyperscale cloud companies has changed that. Leading datacenters have architected, specified or even built (in Google’s case) their own infrastructure, though many large cloud datacenters have been equipped with hyperscale-specific systems from Dell and HP. But more and more systems built exactly to datacenter specifications are coming from suppliers like Quanta. Newer network suppliers like Arista have increased market share. Some new hyperscale solution vendors have emerged, like Nebula. And software has shifted to open source, sometimes supported for-pay by companies copying the Redhat® Linux model – companies like Cloudera, Mirantis or United Stack. Personally, I am still waiting for the first 3rd-party hardware service emulating a Linux support and service company to appear.

Open initiatives: Yes, we’ve seen Hadoop and its derivatives deployed everywhere now – even in traditional industries like oil and gas, pharmacology, genomics, etc. And we’ve seen the emergence of open-source alternatives to traditional databases being deployed, like Casandra. But now we’re seeing new initiatives like Open Compute and OpenStack. Sure these are helpful to hyperscale datacenters, but they are also enabling smaller companies and universities to deploy hyperscale-like infrastructure and get the same kind of automated control, efficiency and cost structures that hyperscale datacenters enjoy. (Of course they don’t get fully there on any front, but it’s a lot closer). This trend has the potential to hurt OEM and ISV business models and markets and establish new entrants – even as we see Quanta, TYAN, Foxconn, Wistron and others tentatively entering the broader market through these open initiatives.

New architectures and new algorithms: There is a clear movement toward pooled resources (or rack scale architecture, or disaggregated servers). Developing pooled resource solutions has become a partnership between core IP providers like Intel and LSI with the largest hyperscale datacenter architects. Traditionally new architectures were driven by OEMs, but that is not so true anymore. We are seeing new technologies emerge to enable these rack-scale architectures (RSA) – technologies like silicon photonics, pooled storage, software-defined networks (SDN), and we will soon see pooled main memory and new nonvolatile main memories in the rack.

We are also seeing the first tries at new processor architectures about to enter the datacenter: ARM 64 for cool/cold storage and web tier and OpenPower P8 for high power processing – multithreaded, multi-issue, pooled memory processing monsters. This is exciting to watch. There is also an emerging interest in application acceleration: general-purposing computing on graphics processing units (GPGPUs), regular expression processors (regex) live stream analytics, etc. We are also seeing the first generation of graph analysis deployed at massive scale in real time.

Innovation: The pace of innovation appears to be accelerating, although maybe I’m just getting older. But the easy gains are done. On one hand, datacenters need exponentially more compute and storage, and they need to operate 10x to 1000x more quickly. On the other, memory, processor cores, disks and flash technologies are getting no faster. The only way to fill that gap is through innovation. So it’s no surprise there are lots of interesting things happening at OEMs and ISVs, chip and solution companies, as well as open source community and startups. This is what makes it such an interesting time and industry.

Consumption shifts: We are seeing a decline in laptop and personal computer shipments, a drop that naturally is reducing storage demand in those markets. Laptops are also seeing a shift to SSD from HDD. This has been good for LSI, as our footprint in laptop HDDs had been small, but our presence in laptop SSDs is very strong. Smart phones and tablets are driving more cloud content, traffic and reliance on cloud storage. We have seen a dramatic increase in large HDDs for cloud storage, a trend that seems to be picking up speed, and we believe the cloud HDD market will be very healthy and will see the emergence of new, cloud-specific HDDs that are radically different and specifically designed for cool and cold storage.

There is also an explosion of SSD and PCIe flash cards in cloud computing for databases, caches, low-latency access and virtual machine (VM) enablement. Many applications that we take for granted would not be possible without these extreme low-latency, high-capacity flash products. But very few companies can make a viable storage system from flash at an acceptable cost, opening up an opportunity for many startups to experiment with different solutions.

Summary: So I believe the biggest hyperscale innovations are autonomous behavior and orchestration, HA at the datacenter level vs. machine level, and big data. These are radically changing the whole industry. And what are those changes for our industry and ecosystem? You name it: timing, end customers, new players, open initiatives, new architectures and algorithms, innovation, and consumption patterns. All that’s staying the same are legacy products and solutions.

These were great questions. Sometimes you need the press or someone outside the industry to ask a question that makes you step back and think about what’s going on. Great questions.

Restructuring the datacenter ecosystem (Part 2)

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Pushing your enterprise cluster solution to deliver the highest performance at the lowest cost is key in architecting scale-out datacenters. Administrators must expand their storage to keep pace with their compute power as capacity and processing demands grow.

safijidsjfijdsifjiodsjfiosjdifdsoijfdsoijfsfkdsjifodsjiof dfisojfidosj iojfsdiojofodisjfoisdjfiodsj ofijds fds foids gfd gfd gfd gfd gfd gfd gfd gfd gfd gfdg dfg gfdgfdg fd gfd gdf gfd gdfgdf g gfd gdfg dfgfdg fdgfdgBeyond price and capacity, storage resources must also deliver enough bandwidth to support these growing demands. Without enough I/O bandwidth, connected servers and users can bottleneck, requiring sophisticated storage tuning to maintain reasonable performance. By using direct attached storage (DAS) server architectures, IT administrators can

Diagram of DataBolt technology buffering 6Gb/s SAS media while maintaining a 12Gb/s SAS link.

Beyond price and capacity, storage resources must also deliver enough bandwidth to support these growing demands. Without enough I/O bandwidth, connected servers and users can bottleneck, requiring sophisticated storage tuning to maintain reasonable performance. By using direct attached storage (DAS) server architectures, IT administrators can reduce the complexities and performance latencies associated with storage area networks (SANs). Now, with LSI 12Gb/s SAS or MegaRAID® technology, or both, connected to 12Gb/s SAS expander-based storage enclosures, administrators can leverage the DataBolt™ technology to clear I/O bandwidth bottlenecks. The result: better overall resource utilization, while preserving legacy drive investments. Typically a slower end device would step down the entire 12Gb/s SAS storage subsystem to 6Gb/s SAS speeds. How does Databolt technology overcome this? Well, without diving too deep into the nuts and bolts, intelligence in the expander buffers data and then transfers it out to the drives at 6Gb/s speeds in order to match the bandwidth between faster hosts and slower SAS or SATA devices.

The DataBolt enabled Hadoop server bandwidth is optimized with 12Gb/s SAS.

So for this demonstration at AIS, we are showcasing two Hadoop Distributed File System (HDFS) servers. Each server houses the newly shipping MegaRAID 9361-8i 12Gb/s SAS RAID controller connected to a drive enclosure featuring a 12Gb/s SAS expander and 32 6Gb/s SAS hard drives. One has a DataBolt-enabled configuration, while the other is disabled.

For the benchmarks, we ran DFSIO, which simulates MapReduce workloads and is typically used to detect performance network bottlenecks and tune hardware configurations as well as overall I/O performance.

The primary goal of the DFSIO benchmarks is to saturate storage arrays with random read workloads in order to ensure maximum performance of a cluster configuration. Our tests resulted in MapReduce Jobs completing faster in 12Gb/s mode, and overall throughput increased by 25%.

DataBolt optimization of DFSIO MapReduce tests (MB/s) per cluster slot maps.

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Lenovo is whopping big. The planet’s second largest PC maker, the sixth largest server vendor and China’s top server supplier.

So when a big gun like Lenovo recognizes us with its Technology Innovation award for our 12G SAS technology, we love to talk about it. The lofty honor came at the recent Lenovo Supplier Conference in Hefei, China.

Hefei is big too. As recently at the mid-1930’s, Hefei was a quiet market town of only about 30,000. Today, it’s home to more than 7 million people spread across 4,300 square miles. No matter how you cut it, that’s explosive growth – and no less dizzying than the global seam-splitting growth that Lenovo is helping companies worldwide manage with its leading servers.

For more than a decade, LSI has been the SAS/RAID strategic partner for Lenovo and in 2009 it chose LSI as its exclusive SAS/RAID vendor. The reason: Our ability to provide enterprise class and industry-leading SAS/RAID solutions.  Lenovo says it better.

“In 2012, Lenovo began to sharpen its focus on the enterprise server business with the goal of becoming a tier-1 server in the global market,” said Jack Xing, senior sales manager in China. ”To support this strategy, the company realized the importance of selecting a trusted and innovative SAS/RAID partner, which is why it has turned to LSI exclusively for its 12G SAS technology.”

Trust. Innovation. High compliments from Lenovo, a major engine of technology innovation in one of the world’s fastest-growing economies. It’s dizzying, even heady. You can see why we love to talk about it.

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Big data and Hadoop are all about exploiting new value and opportunities with data. In financial trading, business and some areas of science, it’s all about being fastest or first to take advantage of the data. The bigger the data sets, the smarter the analytics. The next competitive edge with big data comes when you layer in flash acceleration. The challenge is scaling performance in Hadoop clusters.

The most cost-effective option emerging for breaking through disk-to-I/O bottlenecks to scale performance is to use high-performance read/write flash cache acceleration cards for caching. This is essentially a way to get more work for less cost, by bringing data closer to the processing. The LSI® Nytro™ product has been shown during testing to improve the time it takes to complete Hadoop software framework jobs up to a 33%.

Flash cache cards increase Hadoop application performance
Combining flash cache acceleration cards with Hadoop software is a big opportunity for end users and suppliers. LSI estimates that less than 10% of Hadoop software installations today incorporate flash acceleration1.  This will grow rapidly as companies see the increased productivity and ROI of flash to accelerate their systems.  And Hadoop software adoption is also growing fast. IDC predicts a CAGR of as much as 60% by 20162. Drivers include IT security, e-commerce, fraud detection and mobile data user management. Gartner predicts that Hadoop software will be in two-thirds of advanced analytics products by 20153. Many thousands of Hadoop software clusters are already deployed.

Where flash makes the most immediate sense is with those who have smaller clusters doing lots of in-place batch processing. Hadoop is purpose-built for analyzing a variety of data, whether structured, semi-structured or unstructured, without the need to define a schema or otherwise anticipate results in advance. Hadoop enables scaling that allows an unprecedented volume of data to be analyzed quickly and cost-effectively on clusters of commodity servers. Speed gains are about data proximity. This is why flash cache acceleration typically delivers the highest performance gains when the card is placed directly in the server on the PCI Express® (PCIe) bus.

Combining the best of flash and HDDs to drive higher performance and storage capacity
PCIe flash cache cards are now available with multiple terabytes of NAND flash storage, which substantially increases the hit rate. We offer a solution with both onboard flash modules and Serial-Attached SCSI (SAS) interfaces to enable high-performance direct-attached storage (DAS) configurations consisting of solid state and hard disk drive storage. This couples the low-latency performance benefits of flash with the capacity and cost-per-gigabyte advantages of HDDs.

To keep the processor close to the data, Hadoop uses servers with DAS. And to get the data even closer to the processor, the servers are usually equipped with significant amounts of random access memory (RAM). An additional benefit: Smart implementation of Hadoop and flash components can reduce the overall server footprint and simplify scaling, with some solutions enabling up to 128 devices to share a very high bandwidth interface. Most commodity servers provide 8 or less SATA ports for disks, reducing expandability.

Hadoop is great, but flash-accelerated Hadoop is best. It’s an effective way, as you work to extract full value from big data, to secure a competitive edge.

  1. Based on internal LSI research.
  2. “IDC Worldwide Hadoop-MapReduce Ecosystem Software 2012-2016 Forecast,” May 2012.
  3. “Gartner Predicts 2013: Business Intelligence and Analytics Need to Scale Up to Support Explosive Growth in Data Sources,” December 2012.

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There’s no need to wait for higher speed. Server builders can take advantage of 12Gb/s SAS now. And this is even as HDD and SSD makers continue to tweak, tune and otherwise prepare their 12Gb/s SAS products for market. The next generation of 12Gb/s SAS without supporting drives? What gives?

It’s simple. LSI is already producing 12Gb/s ROC and IOC solutions, meaning that customers can take advantage of 12Gb/s SAS performance today with currently shipping systems and storage.  As for the numbers, LSI 12Gb/s SAS enables performance increases of up to 45% in throughput and up to 58% in IOPS when compared to 6Gb/s SAS.

True, 12Gb/s SAS isn’t a Big Bang Disruption in storage systems; rather it’s an evolutionary change, but a big step forward.  It may not be clear why it matters so much, so I want to briefly explain.  In latest generation PCIe 3 systems, 6Gb/s SAS is the bottleneck that prevents systems from achieving full PCIe 3 throughput of 6,400 MB/s.

With 12Gb/s SAS, customers will be able to take full advantage of the performance of PCIe 3 systems.  Earlier this month at CeBIT computer expo in Hanover, Germany, we announced that we are the first to ship production-level 12Gb/s SAS ROC (RAID on Chip) and IOC (I/O Controllers) to OEM customers.  This convergence of new technologies and the expansion of existing capabilities create significant improvements for datacenters of all kinds.

12Gb/s SAS is required to take full advantage of PCIe 3.0 performance.

At CeBIT, we demonstrated our 12Gb/s SAS solutions with the unique DataBoltTM feature and how, with DataBolt,  systems with 6Gb/s SAS HDDs can achieve 12Gb/s SAS performance.

CeBIT Demo – PCIe 3, 12Gb/s SAS system, using 6Gb/s HDDs

DataBolt uses bandwidth aggregation to create throughput performance acceleration.  Most importantly, customers don’t have to wait for the next inflection in drive design to get the highest possible performance and connectivity.

With 6Gb/s SAS, the maximum throughput of PCIe 3 cannot be attained. SAS is a bottleneck (Left). LSI 12Gb/s SAS clears the SAS bottleneck, enabling full PCIe 3 performance (Right).

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I’ve spent a lot of time with hyperscale datacenters around the world trying to understand their problems – and I really don’t care what area those problems are as long as they’re important to the datacenter. What is the #1 Real Problem for many hyperscale datacenters? It’s something you’ve probably never heard about, and probably have not even thought about. It’s called false disk failure. Some hyperscale datacenters have crafted their own solutions – but most have not.

Why is this important, you ask? Many large datacenters today have 1 million to 4 million hard disk drives (HDDs) in active operation. In anyone’s book that’s a lot. It’s also a very interesting statistical sample size of HDDs. Hyperscale datacenters get great pricing on HDDs. Probably better than OEMs get, and certainly better than the $79 for buying 1 HDD at your local Fry’s store. So you would imagine if a disk fails – no one cares – they’re cheap and easy to replace. But the burden of a failed disk is much more than the raw cost of the disk:

  • Disk rebuild and/or data replicate of 2TB or 3TB drive
    • Performance overhead of a RAID rebuild makes it difficult to justify, and can take days
    • Disk capacity must be added somewhere to compensate: ~$40-$50
    • Redistribute replicated data across many servers
    • Infrastructure overhead to rebalance workloads to other distributed servers
    • Person to service disk: remove and replace
      • And then ensure the HDD data cannot be accessed – wipe it or shred it

Let’s put some scale to this problem, and you’ll begin to understand the issue.  One modest size hyperscale datacenter has been very generous in sharing its real numbers. (When I say modest, they are ~1/4 to 1/2 the size of many other hyperscale datacenters, but they are still huge – more than 200k servers). Other hyperscale datacenters I have checked with say – yep, that’s about right. And one engineer I know at an HDD manufacturer said – “wow – I expected worse than that. That’s pretty good.” To be clear – these are very good HDDs they are using, it’s just that the numbers add up.

The raw data:

RAIDed SAS HDDs

  • 300k SAS HDDs
  • 15-30 SAS failed per day
    • SAS false fail rate is about 30%~45% (10-15 per day)
    • About 1/1000 HDD annual false failure rate

Non-RAIDed (direct map) SATA drives behind HBAs

  • 1.2M SATA HDDs
  • 60-80 SATA failed disks per day
    • SATA false fail rate is about 40~55% (24-40 per day)
    • About 1/100 HDD annual false failure rate

What’s interesting is the relative failure rate of SAS drives vs. SATA. It’s about an order of magnitude worse in SATA drives than SAS. Frankly some of this is due to protocol differences. SAS allows far more error recovery capabilities, and because they also tend to be more expensive, I believe manufacturers invest in slightly higher quality electronics and components. I know the electronics we ship into SAS drives is certainly more sophisticated than SATA drives.

False fail? What? Yea, that’s an interesting topic. It turns out that about 40% of the time with SAS and about 50% of the time with SATA, the drive didn’t actually fail. It just lost its marbles for a while. When they pull the drive out and put it into a test jig, everything is just fine. And more interesting, when they put the drive back into service, it is no more statistically likely to fail again than any other drive in the datacenter. Why? No one knows. I suspect though.

I used to work on engine controllers. That’s a very paranoid business. If something goes wrong and someone crashes, you have a lawsuit on your hands. If a controller needs a recall, that’s millions of units to replace, with a multi-hundred dollar module, and hundreds of dollars in labor for each one replaced. No one is willing to take that risk. So we designed very carefully to handle soft errors in memory and registers. We incorporated ECC like servers use, background code checksums and scrubbing, and all sorts of proprietary techniques, including watchdogs and super-fast self-resets that could get operational again in less than a full revolution of the engine.  Why? – the events were statistically rare. The average controller might see 1 or 2 events in its lifetime, and a turn of the ignition would reset that state.  But the events do happen, and so do recalls and lawsuits… HDD controllers don’t have these protections, which is reasonable. It would be an inappropriate cost burden for their price point.

You remember the Toyota Prius accelerator problems? I know that controller was not protected for soft errors. And the source of the problem remained a “mystery.”  Maybe it just lost its marbles for a while? A false fail if you will. Just sayin’.

Back to HDDs. False fail is especially frustrating, because half the HDDs actually didn’t need to be replaced. All the operational costs were paid for no reason. The disk just needed a power cycle reset. (OK, that introduces all sorts of complex management by the RAID controller or application to manage that 10 second power reset cycle and application traffic created in that time – be we can handle that.)

Daily, this datacenter has to:

  • Physically replace 100 disk drives
    • Individually destroy or recycle the 100 failed drives
    • Replicate or rebuild 200-300 TBytes of data – just think about that
    • Rebalance the application load on at least 100 servers – more likely 100 clusters of servers – maybe 20,000 servers?
    • Handle the network traffic  load of ~200 TBytes of replicated data
      • That’s on the order of 50 hours of 10GBit Ethernet traffic…

And 1/2 of that is for no reason at all.

First – why not rebuild the disk if it’s RAIDed? Usually hyperscale datacenters use clustered applications. A traditional RAID rebuild drives the server performance to ~50%, and for a 2TByte drive, under heavy application load (definition of a hyperscale datacenter) can truly take up to a week.  50% performance for a week? In a cluster that means the overall cluster is running ~50% performance.  Say 200 nodes in a cluster – that means you just lost ~100 nodes of work – or 50% of cluster performance. It’s much simpler to just take the node offline with the failed drive, and get 99.5% cluster performance, and operationally redistribute the workload across multiple nodes (because you have replicated data elsewhere). But after rebuild, the node will have to be re-synced or re-imaged. There are ways to fix all this. We’ll talk about them on another day. Or you can simply run direct mapped storage, and unmounts the failed drive.

Next – Why replicate data over the network, and why is that a big deal? For geographic redundancy (say a natural disaster at one facility) and regional locality, hyperscale datacenters need multiple data copies. Often 3 copies so they can do double duty as high-availability copies, or in the case of some erasure coding, 2.2 to 2.5 copies (yea – weird math – how do you have 0.5 copy…). When you lose one copy, you are down to 2, possibly 1. You need to get back to a reliable number again. Fast. Customers are loyal because of your perfect data retention. So you need to replicate that data and re-distribute it across the datacenter on multiple servers. That’s network traffic, and possibly congestion, which affects other aspects of the operations of the datacenter. In this datacenter it’s about 50 hours of 10G Ethernet traffic every day.

To be fair, there is a new standard in SAS interfaces that will facilitate resetting a disk in-situ. And there is the start of discussion of the same around SATA – but that’s more problematic. Whatever the case, it will be a years before the ecosystem is in place to handle the problems this way.

What’s that mean to you?

Well. You can expect something like 1/100 of your drives to really fail this year. And you can expect another 1/100 of your drives to fail this year, but not actually be failed. You’ll still pay all the operational overhead of not actually having a failed drive – rebuilds, disk replacements, management interventions, scheduled downtime/maintenance time, and the OEM replacement price for that drive – what $600 or so ?… Depending on your size, that’s either a don’t care, or a big deal. There are ways to handle this, and they’re not expensive – much less than the disk carrier you already pay for to allow you to replace that drive – and it can be handled transparently – just a log entry without seeing any performance hiccups.  You just need to convince your OEM to carry the solution.

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