|By Nikita Ivanov||
|December 29, 2014 12:00 PM EST||
A few months ago, I spoke at the conference where I explained the difference between caching and an in-memory data grid. Today, having realized that many people are also looking to better understand the difference between two major categories in in-memory computing: In-Memory Database and In-Memory Data Grid, I am sharing the succinct version of my thinking on this topic - thanks to a recent analyst call that helped to put everything in place
Skip to conclusion to get the bottom line.
Let's clarify the naming and buzzwords first. In-Memory Database (IMDB) is a well-established category name and it is typically used unambiguously.
It is important to note that there is a new crop of traditional databases with serious In-Memory "options". That includes MS SQL 2014, Oracle's Exalytics and Exadata, and IBM DB2 with BLU offerings. The line is blurry between these and the new pure In-Memory Databases, and for the simplicity I'll continue to call them In-Memory Databases.
In-Memory Data Grids (IMDGs) are sometimes (but not very frequently) called In-Memory NoSQL/NewSQL Databases. Although the latter can be more accurate in some case - I am going to use the In-Memory Data Grid term in this article, as it tends to be the more widely used term.
Note that there are also In-Memory Compute Grids and In-Memory Computing Platforms that include or augment many of the features of In-Memory Data Grids and In-Memory Databases.
Confusing, eh? It is... and for consistency - going forward we'll just use these terms for the two main categories:
- In-Memory Database
- In-Memory Data Grid
It is also important to nail down what we mean by "In-Memory". Surprisingly - there's a lot of confusion here as well as some vendors refer to SSDs, Flash-on-PCI, Memory Channel Storage, and, of course, DRAM as "In-Memory".
In reality, most vendors support a Tiered Storage Model where some portion of the data is stored in DRAM (the fastest storage but with limited capacity) and then it gets overflown to a verity of flash or disk devices (slower but with more capacity) - so it is rarely a DRAM-only or Flash-only product. However, it's important to note that most products in both categories are often biased towards mostly DRAM or mostly flash/disk storage in their architecture.
Bottom line is that products vary greatly in what they mean by "In-Memory" but in the end they all have a significant "In-Memory" component.
It's easy to start with technical differences between the two categories.
Most In-Memory Databases are your father's RDBMS that store data "in memory" instead of disk. That's practically all there's to it. They provide good SQL support with only a modest list of unsupported SQL features, shipped with ODBC/JDBC drivers and can be used in place of existing RDBMS often without significant changes.
In-Memory Data Grids typically lack full ANSI SQL support but instead provide MPP-based (Massively Parallel Processing) capabilities where data is spread across large cluster of commodity servers and processed in explicitly parallel fashion. The main access pattern is key/value access, MapReduce, various forms of HPC-like processing, and a limited distributed SQL querying and indexing capabilities.
It is important to note that there is a significant crossover from In-Memory Data Grids to In-Memory Databases in terms of SQL support. GridGain, for example, provides pretty serious and constantly growing support for SQL including pluggable indexing, distributed joins optimization, custom SQL functions, etc.
Speed Only vs. Speed + Scalability
One of the crucial differences between In-Memory Data Grids and In-Memory Databases lies in the ability to scale to hundreds and thousands of servers. That is the In-Memory Data Grid's inherent capability for such scale due to their MPP architecture, and the In-Memory Database's explicit inability to scale due to fact that SQL joins, in general, cannot be efficiently performed in a distribution context.
It's one of the dirty secrets of In-Memory Databases: one of their most useful features, SQL joins, is also is their Achilles heel when it comes to scalability. This is the fundamental reason why most existing SQL databases (disk or memory based) are based on vertically scalable SMP (Symmetrical Processing) architecture unlike In-Memory Data Grids that utilize the much more horizontally scalable MPP approach.
It's important to note that both In-Memory Data Grids and In-Memory Database can achieve similar speed in a local non-distributed context. In the end - they both do all processing in memory.
But only In-Memory Data Grids can natively scale to hundreds and thousands of nodes providing unprecedented scalability and unrivaled throughput.
Replace Database vs. Change Application
Apart from scalability, there is another difference that is important for uses cases where In-Memory Data Grids or In-Memory Database are tasked with speeding up existing systems or applications.
An In-Memory Data Grid always works with an existing database providing a layer of massively distributed in-memory storage and processing between the database and the application. Applications then rely on this layer for super-fast data access and processing. Most In-Memory Data Grids can seamlessly read-through and write-through from and to databases, when necessary, and generally are highly integrated with existing databases.
In exchange - developers need to make some changes to the application to take advantage of these new capabilities. The application no longer "talks" SQL only, but needs to learn how to use MPP, MapReduce or other techniques of data processing.
In-Memory Databases provide almost a mirror opposite picture: they often requirereplacing your existing database (unless you use one of those In-Memory "options" to temporary boost your database performance) - but will demand significantly less changes to the application itself as it will continue to rely on SQL (albeit a modified dialect of it).
In the end, both approaches have their advantages and disadvantages, and they may often depend in part on organizational policies and politics as much as on their technical merits.
The bottom line should be pretty clear by now.
If you are developing a green-field, brand new system or application the choice is pretty clear in favor of In-Memory Data Grids. You get the best of the two worlds: you get to work with the existing databases in your organization where necessary, and enjoy tremendous performance and scalability benefits of In-Memory Data Grids - both of which are highly integrated.
If you are, however, modernizing your existing enterprise system or application the choice comes down to this:
You will want to use an In-Memory Database if the following applies to you:
- You can replace or upgrade your existing disk-based RDBMS
- You cannot make changes to your applications
- You care about speed, but don't care as much about scalability
In other words - you boost your application's speed by replacing or upgrading RDBMS without significantly touching the application itself.
On the other hand, you want to use an In-Memory Data Grid if the following applies to you:
- You cannot replace your existing disk-based RDBMS
- You can make changes to (the data access subsystem of) your application
- You care about speed and especially about scalability, and don't want to trade one for the other
In other words - with an In-Memory Data Grid you can boost your application's speed and provide massive scale by tweaking the application, but without making changes to your existing database.
It can be summarized it in the following table:
|In-Memory Data Grid||In-Memory Database|
|Existing RDBMS||Unchanged||Changed or Replaced|
DevOps Summit 2015 New York, co-located with the 16th International Cloud Expo - to be held June 9-11, 2015, at the Javits Center in New York City, NY - announces that it is now accepting Keynote Proposals. The widespread success of cloud computing is driving the DevOps revolution in enterprise IT. Now as never before, development teams must communicate and collaborate in a dynamic, 24/7/365 environment. There is no time to wait for long development cycles that produce software that is obsolete at launch. DevOps may be disruptive, but it is essential.
Jan. 30, 2015 01:15 PM EST Reads: 2,590
Wearable devices have come of age. The primary applications of wearables so far have been "the Quantified Self" or the tracking of one's fitness and health status. We propose the evolution of wearables into social and emotional communication devices. Our BE(tm) sensor uses light to visualize the skin conductance response. Our sensors are very inexpensive and can be massively distributed to audiences or groups of any size, in order to gauge reactions to performances, video, or any kind of presentation. In her session at @ThingsExpo, Jocelyn Scheirer, CEO & Founder of Bionolux, will discuss ho...
Jan. 30, 2015 01:15 PM EST Reads: 2,005
Almost everyone sees the potential of Internet of Things but how can businesses truly unlock that potential. The key will be in the ability to discover business insight in the midst of an ocean of Big Data generated from billions of embedded devices via Systems of Discover. Businesses will also need to ensure that they can sustain that insight by leveraging the cloud for global reach, scale and elasticity.
Jan. 30, 2015 01:00 PM EST Reads: 4,114
“With easy-to-use SDKs for Atmel’s platforms, IoT developers can now reap the benefits of realtime communication, and bypass the security pitfalls and configuration complexities that put IoT deployments at risk,” said Todd Greene, founder & CEO of PubNub. PubNub will team with Atmel at CES 2015 to launch full SDK support for Atmel’s MCU, MPU, and Wireless SoC platforms. Atmel developers now have access to PubNub’s secure Publish/Subscribe messaging with guaranteed ¼ second latencies across PubNub’s 14 global points-of-presence. PubNub delivers secure communication through firewalls, proxy ser...
Jan. 30, 2015 12:45 PM EST Reads: 1,700
We’re no longer looking to the future for the IoT wave. It’s no longer a distant dream but a reality that has arrived. It’s now time to make sure the industry is in alignment to meet the IoT growing pains – cooperate and collaborate as well as innovate. In his session at @ThingsExpo, Jim Hunter, Chief Scientist & Technology Evangelist at Greenwave Systems, will examine the key ingredients to IoT success and identify solutions to challenges the industry is facing. The deep industry expertise behind this presentation will provide attendees with a leading edge view of rapidly emerging IoT oppor...
Jan. 30, 2015 12:45 PM EST Reads: 1,908
The 3rd International Internet of @ThingsExpo, co-located with the 16th International Cloud Expo - to be held June 9-11, 2015, at the Javits Center in New York City, NY - announces that its Call for Papers is now open. The Internet of Things (IoT) is the biggest idea since the creation of the Worldwide Web more than 20 years ago.
Jan. 30, 2015 12:00 PM EST Reads: 8,020
Connected devices and the Internet of Things are getting significant momentum in 2014. In his session at Internet of @ThingsExpo, Jim Hunter, Chief Scientist & Technology Evangelist at Greenwave Systems, examined three key elements that together will drive mass adoption of the IoT before the end of 2015. The first element is the recent advent of robust open source protocols (like AllJoyn and WebRTC) that facilitate M2M communication. The second is broad availability of flexible, cost-effective storage designed to handle the massive surge in back-end data in a world where timely analytics is e...
Jan. 30, 2015 12:00 PM EST Reads: 2,629
"There is a natural synchronization between the business models, the IoT is there to support ,” explained Brendan O'Brien, Co-founder and Chief Architect of Aria Systems, in this SYS-CON.tv interview at the 15th International Cloud Expo®, held Nov 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA.
Jan. 30, 2015 11:45 AM EST Reads: 3,610
The Internet of Things will put IT to its ultimate test by creating infinite new opportunities to digitize products and services, generate and analyze new data to improve customer satisfaction, and discover new ways to gain a competitive advantage across nearly every industry. In order to help corporate business units to capitalize on the rapidly evolving IoT opportunities, IT must stand up to a new set of challenges. In his session at @ThingsExpo, Jeff Kaplan, Managing Director of THINKstrategies, will examine why IT must finally fulfill its role in support of its SBUs or face a new round of...
Jan. 30, 2015 11:45 AM EST Reads: 2,754
The BPM world is going through some evolution or changes where traditional business process management solutions really have nowhere to go in terms of development of the road map. In this demo at 15th Cloud Expo, Kyle Hansen, Director of Professional Services at AgilePoint, shows AgilePoint’s unique approach to dealing with this market circumstance by developing a rapid application composition or development framework.
Jan. 30, 2015 11:30 AM EST Reads: 2,288
The Internet of Things will greatly expand the opportunities for data collection and new business models driven off of that data. In her session at @ThingsExpo, Esmeralda Swartz, CMO of MetraTech, discussed how for this to be effective you not only need to have infrastructure and operational models capable of utilizing this new phenomenon, but increasingly service providers will need to convince a skeptical public to participate. Get ready to show them the money!
Jan. 30, 2015 11:30 AM EST Reads: 3,047
ARMONK, N.Y., Nov. 20, 2014 /PRNewswire/ -- IBM (NYSE: IBM) today announced that it is bringing a greater level of control, security and flexibility to cloud-based application development and delivery with a single-tenant version of Bluemix, IBM's platform-as-a-service. The new platform enables developers to build ap...
Jan. 30, 2015 11:15 AM EST Reads: 3,118
Building low-cost wearable devices can enhance the quality of our lives. In his session at Internet of @ThingsExpo, Sai Yamanoor, Embedded Software Engineer at Altschool, provided an example of putting together a small keychain within a $50 budget that educates the user about the air quality in their surroundings. He also provided examples such as building a wearable device that provides transit or recreational information. He then reviewed the resources available to build wearable devices at home including open source hardware, the raw materials required and the options available to power s...
Jan. 30, 2015 11:00 AM EST Reads: 2,417
The Internet of Things is not new. Historically, smart businesses have used its basic concept of leveraging data to drive better decision making and have capitalized on those insights to realize additional revenue opportunities. So, what has changed to make the Internet of Things one of the hottest topics in tech? In his session at @ThingsExpo, Chris Gray, Director, Embedded and Internet of Things, discussed the underlying factors that are driving the economics of intelligent systems. Discover how hardware commoditization, the ubiquitous nature of connectivity, and the emergence of Big Data a...
Jan. 30, 2015 10:45 AM EST Reads: 3,204
The Internet of Things promises to transform businesses (and lives), but navigating the business and technical path to success can be difficult to understand. In his session at @ThingsExpo, Sean Lorenz, Technical Product Manager for Xively at LogMeIn, demonstrated how to approach creating broadly successful connected customer solutions using real world business transformation studies including New England BioLabs and more.
Jan. 30, 2015 10:45 AM EST Reads: 2,669
We certainly live in interesting technological times. And no more interesting than the current competing IoT standards for connectivity. Various standards bodies, approaches, and ecosystems are vying for mindshare and positioning for a competitive edge. It is clear that when the dust settles, we will have new protocols, evolved protocols, that will change the way we interact with devices and infrastructure. We will also have evolved web protocols, like HTTP/2, that will be changing the very core of our infrastructures. At the same time, we have old approaches made new again like micro-services...
Jan. 30, 2015 10:30 AM EST Reads: 2,535
Enthusiasm for the Internet of Things has reached an all-time high. In 2013 alone, venture capitalists spent more than $1 billion dollars investing in the IoT space. With "smart" appliances and devices, IoT covers wearable smart devices, cloud services to hardware companies. Nest, a Google company, detects temperatures inside homes and automatically adjusts it by tracking its user's habit. These technologies are quickly developing and with it come challenges such as bridging infrastructure gaps, abiding by privacy concerns and making the concept a reality. These challenges can't be addressed w...
Jan. 30, 2015 10:00 AM EST Reads: 3,184
The Domain Name Service (DNS) is one of the most important components in networking infrastructure, enabling users and services to access applications by translating URLs (names) into IP addresses (numbers). Because every icon and URL and all embedded content on a website requires a DNS lookup loading complex sites necessitates hundreds of DNS queries. In addition, as more internet-enabled ‘Things' get connected, people will rely on DNS to name and find their fridges, toasters and toilets. According to a recent IDG Research Services Survey this rate of traffic will only grow. What's driving t...
Jan. 30, 2015 10:00 AM EST Reads: 3,213
The Internet of Things is a misnomer. That implies that everything is on the Internet, and that simply should not be - especially for things that are blurring the line between medical devices that stimulate like a pacemaker and quantified self-sensors like a pedometer or pulse tracker. The mesh of things that we manage must be segmented into zones of trust for sensing data, transmitting data, receiving command and control administrative changes, and peer-to-peer mesh messaging. In his session at @ThingsExpo, Ryan Bagnulo, Solution Architect / Software Engineer at SOA Software, focused on desi...
Jan. 30, 2015 10:00 AM EST Reads: 2,394
Today’s enterprise is being driven by disruptive competitive and human capital requirements to provide enterprise application access through not only desktops, but also mobile devices. To retrofit existing programs across all these devices using traditional programming methods is very costly and time consuming – often prohibitively so. In his session at @ThingsExpo, Jesse Shiah, CEO, President, and Co-Founder of AgilePoint Inc., discussed how you can create applications that run on all mobile devices as well as laptops and desktops using a visual drag-and-drop application – and eForms-buildi...
Jan. 30, 2015 10:00 AM EST Reads: 2,873