Welcome!

IBM Cloud Authors: Liz McMillan, Elizabeth White, Aruna Ravichandran, Anders Wallgren, SmartBear Blog

Related Topics: Java IoT, Industrial IoT, Adobe Flex, IoT User Interface, Recurring Revenue, Apache

Java IoT: Blog Feed Post

Debunking DRAM vs. Flash Controversy vis-a-vis In-Memory Processing

“Minimal” Performance Advantage of DRAM vs SSD

Wikibon produced an interesting material (looks like paid by Aerospike, NoSQL database recently emerged by resurrecting failed CitrusLeaf and acquihiring AlchemyDB, which product, of course, was recommended in the end) that compares NoSQL databases based on storing data in flash-based SSD vs. storing data in DRAM.

There are number of factual problems with that paper and I want to point them out.

Note that Wikibon doesn’t mention GridGain in this study (we are not a NoSQL datastore per-se after all) so I don’t have any bone in this game other than annoyance with biased and factually incorrect writing.

“Minimal” Performance Advantage of DRAM vs SSD
The paper starts with a simple statement “The minimal performance disadvantage of flash, relative to main memory…”. Minimal? I’ve seen number of studies where performance difference between SSDs and DRAM range form 100 to 10,000 times. For example, this University of California, Berkeley study claims that SSD bring almost no advantage to the Facebook Hadoop cluster and DRAM pre-caching is the way forward.

Let me provide even shorter explanation. Assuming we are dealing with Java – SSD devices are visible to Java application as typical block devices, and therefore accessed as such. It means that a typical object read from such device involves the same steps as reading this object from a file: hardware I/O subsystem, OS I/O subsystem, OS buffering, Java I/O subsystem & buffering, Java deserialization and induced GC. And… if you read the same object from DRAM – it involves few bytecode instructions – and that’s it.

Native C/C++ apps (like MongoDB) can take a slightly quicker route with memory mapped files (or various other IPC methods) – but the performance increase will not be significant (for obvious reason of needing to read/swap the entire pages vs. single object access pattern in DRAM).

Yet another recent technical explanation of the disadvantages of SSD storage can be found here (talking about Oracle’s “in-memory” strategy).

MongoDB, Cassandra, CouchDB DRAM-based?
Amid all the confusion on this topic it’s no wonder the author got it wrong. Neither MongoDB, Cassandra or CouchDB are in-memory systems. They are disk-based systems with support for memory caching. There’s nothing wrong with that and nothing new – every database developed in the last 25 years naturally provides in-memory caching to augment it’s main disk storage.

The fundamental difference here is that in-memory data systems like GridGain, SAP HAHA, GigaSpaces, GemFire, SqlFire, MemSQL, VoltDB, etc. use DRAM (memory) as the main storage medium and use disk for optional durability and overflow. This focus on RAM-based storage allows to completely re-optimized all main algorithms used in these systems.

For example, ACID implementation in GridGain that provides support for full-featured distributed ACID transactions beats every NoSQL database (EC-based) out there in read and even write performance: there are no single key limitations, no consistency trade offs to make, no application-side MVCC, no user-based conflict resolutions or other crutches – it just works the same way as it works in Oracle or DB2 – but faster.

2TB Cluster for $1.2M :)
If there was on piece in the original paper that was completely made up to fit the predefined narrative it was a price comparison. If the author thinks that 2TB RAM cluster costs $1.2M today – I have not one but two Golden Gate bridges to sell just for him…

Let’s see. A typical Dell/HP/IBM/Cisco blade with 256GB of DRAM will cost below $20K if you just buy on the list prices (Cisco seems to offer the best prices starting at around $15K for 256GB blades). That brings the total cost of 2TB cluster well below $200K (with all network and power equipment included and 100s TBs of disk storage).

Is this more expensive that SSD only cluster? Yes, by 2.5-3x times more expensive. But you are getting dramatic performance increase with the right software that more than justifies that price increase.

Conclusion
2-3x times price difference is nonetheless important and it provides our customers a very clear choice. If price is an issue and high performance is not – there are disk-based systems of wide varieties. If high performance and sub-second response on processing TBs of data is required – the hardware will be proportionally more expensive.

However, with 1GB of DRAM costing less than 1 USD and DRAM prices dropping 30% every 18 months – the era of disks (flash or spinning) is clearly coming to its logical end. It’s normal… it’s a progress and we all need to learn how to adapt.

Has anyone seen tape drives lately?

Read the original blog entry...

More Stories By Thomas Krafft

Over 15 years of experience in marketing and demand creation, with strategies driving over $500 million in revenue for a variety of companies in several high-growth and competitive markets, including consumer software and web services, ecommerce, demand creation through web and search, big data, and now healthcare.

@ThingsExpo Stories
Machine Learning helps make complex systems more efficient. By applying advanced Machine Learning techniques such as Cognitive Fingerprinting, wind project operators can utilize these tools to learn from collected data, detect regular patterns, and optimize their own operations. In his session at 18th Cloud Expo, Stuart Gillen, Director of Business Development at SparkCognition, will discuss how research has demonstrated the value of Machine Learning in delivering next generation analytics to im...
So, you bought into the current machine learning craze and went on to collect millions/billions of records from this promising new data source. Now, what do you do with them? Too often, the abundance of data quickly turns into an abundance of problems. How do you extract that "magic essence" from your data without falling into the common pitfalls? In her session at @ThingsExpo, Natalia Ponomareva, Software Engineer at Google, will provide tips on how to be successful in large scale machine lear...
There is an ever-growing explosion of new devices that are connected to the Internet using “cloud” solutions. This rapid growth is creating a massive new demand for efficient access to data. And it’s not just about connecting to that data anymore. This new demand is bringing new issues and challenges and it is important for companies to scale for the coming growth. And with that scaling comes the need for greater security, gathering and data analysis, storage, connectivity and, of course, the...
This is not a small hotel event. It is also not a big vendor party where politicians and entertainers are more important than real content. This is Cloud Expo, the world's longest-running conference and exhibition focused on Cloud Computing and all that it entails. If you want serious presentations and valuable insight about Cloud Computing for three straight days, then register now for Cloud Expo.
IoT device adoption is growing at staggering rates, and with it comes opportunity for developers to meet consumer demand for an ever more connected world. Wireless communication is the key part of the encompassing components of any IoT device. Wireless connectivity enhances the device utility at the expense of ease of use and deployment challenges. Since connectivity is fundamental for IoT device development, engineers must understand how to overcome the hurdles inherent in incorporating multipl...
The increasing popularity of the Internet of Things necessitates that our physical and cognitive relationship with wearable technology will change rapidly in the near future. This advent means logging has become a thing of the past. Before, it was on us to track our own data, but now that data is automatically available. What does this mean for mHealth and the "connected" body? In her session at @ThingsExpo, Lisa Calkins, CEO and co-founder of Amadeus Consulting, will discuss the impact of wea...
SYS-CON Events announced today that Stratoscale, the software company developing the next generation data center operating system, will exhibit at SYS-CON's 18th International Cloud Expo®, which will take place on June 7-9, 2016, at the Javits Center in New York City, NY. Stratoscale is revolutionizing the data center with a zero-to-cloud-in-minutes solution. With Stratoscale’s hardware-agnostic, Software Defined Data Center (SDDC) solution to store everything, run anything and scale everywhere...
Angular 2 is a complete re-write of the popular framework AngularJS. Programming in Angular 2 is greatly simplified – now it's a component-based well-performing framework. This immersive one-day workshop at 18th Cloud Expo, led by Yakov Fain, a Java Champion and a co-founder of the IT consultancy Farata Systems and the product company SuranceBay, will provide you with everything you wanted to know about Angular 2.
SYS-CON Events announced today that Peak 10, Inc., a national IT infrastructure and cloud services provider, will exhibit at SYS-CON's 18th International Cloud Expo®, which will take place on June 7-9, 2016, at the Javits Center in New York City, NY. Peak 10 provides reliable, tailored data center and network services, cloud and managed services. Its solutions are designed to scale and adapt to customers’ changing business needs, enabling them to lower costs, improve performance and focus inter...
You think you know what’s in your data. But do you? Most organizations are now aware of the business intelligence represented by their data. Data science stands to take this to a level you never thought of – literally. The techniques of data science, when used with the capabilities of Big Data technologies, can make connections you had not yet imagined, helping you discover new insights and ask new questions of your data. In his session at @ThingsExpo, Sarbjit Sarkaria, data science team lead ...
SYS-CON Events announced today that Men & Mice, the leading global provider of DNS, DHCP and IP address management overlay solutions, will exhibit at SYS-CON's 18th International Cloud Expo®, which will take place on June 7-9, 2016, at the Javits Center in New York City, NY. The Men & Mice Suite overlay solution is already known for its powerful application in heterogeneous operating environments, enabling enterprises to scale without fuss. Building on a solid range of diverse platform support,...
You deployed your app with the Bluemix PaaS and it's gaining some serious traction, so it's time to make some tweaks. Did you design your application in a way that it can scale in the cloud? Were you even thinking about the cloud when you built the app? If not, chances are your app is going to break. Check out this webcast to learn various techniques for designing applications that will scale successfully in Bluemix, for the confidence you need to take your apps to the next level and beyond.
We’ve worked with dozens of early adopters across numerous industries and will debunk common misperceptions, which starts with understanding that many of the connected products we’ll use over the next 5 years are already products, they’re just not yet connected. With an IoT product, time-in-market provides much more essential feedback than ever before. Innovation comes from what you do with the data that the connected product provides in order to enhance the customer experience and optimize busi...
Increasing IoT connectivity is forcing enterprises to find elegant solutions to organize and visualize all incoming data from these connected devices with re-configurable dashboard widgets to effectively allow rapid decision-making for everything from immediate actions in tactical situations to strategic analysis and reporting. In his session at 18th Cloud Expo, Shikhir Singh, Senior Developer Relations Manager at Sencha, will discuss how to create HTML5 dashboards that interact with IoT devic...
Artificial Intelligence has the potential to massively disrupt IoT. In his session at 18th Cloud Expo, AJ Abdallat, CEO of Beyond AI, will discuss what the five main drivers are in Artificial Intelligence that could shape the future of the Internet of Things. AJ Abdallat is CEO of Beyond AI. He has over 20 years of management experience in the fields of artificial intelligence, sensors, instruments, devices and software for telecommunications, life sciences, environmental monitoring, process...
SYS-CON Events announced today that Ericsson has been named “Gold Sponsor” of SYS-CON's @ThingsExpo, which will take place on June 7-9, 2016, at the Javits Center in New York, New York. Ericsson is a world leader in the rapidly changing environment of communications technology – providing equipment, software and services to enable transformation through mobility. Some 40 percent of global mobile traffic runs through networks we have supplied. More than 1 billion subscribers around the world re...
Digital payments using wearable devices such as smart watches, fitness trackers, and payment wristbands are an increasing area of focus for industry participants, and consumer acceptance from early trials and deployments has encouraged some of the biggest names in technology and banking to continue their push to drive growth in this nascent market. Wearable payment systems may utilize near field communication (NFC), radio frequency identification (RFID), or quick response (QR) codes and barcodes...
In his session at @ThingsExpo, Chris Klein, CEO and Co-founder of Rachio, will discuss next generation communities that are using IoT to create more sustainable, intelligent communities. One example is Sterling Ranch, a 10,000 home development that – with the help of Siemens – will integrate IoT technology into the community to provide residents with energy and water savings as well as intelligent security. Everything from stop lights to sprinkler systems to building infrastructures will run ef...
SYS-CON Events announced today that Fusion, a leading provider of cloud services, will exhibit at SYS-CON's 18th International Cloud Expo®, which will take place on June 7-9, 2016, at the Javits Center in New York City, NY. Fusion, a leading provider of integrated cloud solutions to small, medium and large businesses, is the industry's single source for the cloud. Fusion's advanced, proprietary cloud service platform enables the integration of leading edge solutions in the cloud, including cloud...
SYS-CON Events announced today that DatacenterDynamics has been named “Media Sponsor” of SYS-CON's 18th International Cloud Expo, which will take place on June 7–9, 2016, at the Javits Center in New York City, NY. DatacenterDynamics is a brand of DCD Group, a global B2B media and publishing company that develops products to help senior professionals in the world's most ICT dependent organizations make risk-based infrastructure and capacity decisions.