|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|
SYS-CON Events announced today that CA Technologies has been named “Platinum Sponsor” of SYS-CON's 20th International Cloud Expo®, which will take place on June 6-8, 2017, at the Javits Center in New York City, NY, and the 21st International Cloud Expo®, which will take place October 31-November 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. CA Technologies helps customers succeed in a future where every business – from apparel to energy – is being rewritten by software. From ...
Feb. 28, 2017 02:15 AM EST Reads: 689
Web Real-Time Communication APIs have quickly revolutionized what browsers are capable of. In addition to video and audio streams, we can now bi-directionally send arbitrary data over WebRTC's PeerConnection Data Channels. With the advent of Progressive Web Apps and new hardware APIs such as WebBluetooh and WebUSB, we can finally enable users to stitch together the Internet of Things directly from their browsers while communicating privately and securely in a decentralized way.
Feb. 28, 2017 02:15 AM EST Reads: 5,066
"A lot of times people will come to us and have a very diverse set of requirements or very customized need and we'll help them to implement it in a fashion that you can't just buy off of the shelf," explained Nick Rose, CTO of Enzu, in this SYS-CON.tv interview at 18th Cloud Expo, held June 7-9, 2016, at the Javits Center in New York City, NY.
Feb. 28, 2017 02:15 AM EST Reads: 7,086
DevOps is often described as a combination of technology and culture. Without both, DevOps isn't complete. However, applying the culture to outdated technology is a recipe for disaster; as response times grow and connections between teams are delayed by technology, the culture will die. A Nutanix Enterprise Cloud has many benefits that provide the needed base for a true DevOps paradigm.
Feb. 27, 2017 11:45 PM EST Reads: 903
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 ...
Feb. 27, 2017 11:00 PM EST Reads: 9,165
The Internet of Things will challenge the status quo of how IT and development organizations operate. Or will it? Certainly the fog layer of IoT requires special insights about data ontology, security and transactional integrity. But the developmental challenges are the same: People, Process and Platform and how we integrate our thinking to solve complicated problems. In his session at 19th Cloud Expo, Craig Sproule, CEO of Metavine, demonstrated how to move beyond today's coding paradigm and sh...
Feb. 27, 2017 09:15 PM EST Reads: 4,178
Big Data, cloud, analytics, contextual information, wearable tech, sensors, mobility, and WebRTC: together, these advances have created a perfect storm of technologies that are disrupting and transforming classic communications models and ecosystems. In his session at @ThingsExpo, Erik Perotti, Senior Manager of New Ventures on Plantronics’ Innovation team, provided an overview of this technological shift, including associated business and consumer communications impacts, and opportunities it m...
Feb. 27, 2017 08:00 PM EST Reads: 7,971
WebRTC is about the data channel as much as about video and audio conferencing. However, basically all commercial WebRTC applications have been built with a focus on audio and video. The handling of “data” has been limited to text chat and file download – all other data sharing seems to end with screensharing. What is holding back a more intensive use of peer-to-peer data? In her session at @ThingsExpo, Dr Silvia Pfeiffer, WebRTC Applications Team Lead at National ICT Australia, looked at differ...
Feb. 27, 2017 07:45 PM EST Reads: 7,387
With major technology companies and startups seriously embracing IoT strategies, now is the perfect time to attend @ThingsExpo 2016 in New York. Learn what is going on, contribute to the discussions, and ensure that your enterprise is as "IoT-Ready" as it can be! Internet of @ThingsExpo, taking place June 6-8, 2017, at the Javits Center in New York City, New York, is co-located with 20th Cloud Expo and will feature technical sessions from a rock star conference faculty and the leading industry p...
Feb. 27, 2017 07:30 PM EST Reads: 2,278
SYS-CON Events announced today that IoT Now has been named “Media Sponsor” of SYS-CON's 20th International Cloud Expo, which will take place on June 6–8, 2017, at the Javits Center in New York City, NY. IoT Now explores the evolving opportunities and challenges facing CSPs, and it passes on some lessons learned from those who have taken the first steps in next-gen IoT services.
Feb. 27, 2017 07:15 PM EST Reads: 2,007
SYS-CON Events announced today that WineSOFT will exhibit at SYS-CON's 20th International Cloud Expo®, which will take place on June 6-8, 2017, at the Javits Center in New York City, NY. Based in Seoul and Irvine, WineSOFT is an innovative software house focusing on internet infrastructure solutions. The venture started as a bootstrap start-up in 2010 by focusing on making the internet faster and more powerful. WineSOFT’s knowledge is based on the expertise of TCP/IP, VPN, SSL, peer-to-peer, mob...
Feb. 27, 2017 07:00 PM EST Reads: 2,225
The Internet of Things can drive efficiency for airlines and airports. In their session at @ThingsExpo, Shyam Varan Nath, Principal Architect with GE, and Sudip Majumder, senior director of development at Oracle, discussed the technical details of the connected airline baggage and related social media solutions. These IoT applications will enhance travelers' journey experience and drive efficiency for the airlines and the airports.
Feb. 27, 2017 07:00 PM EST Reads: 2,613
A strange thing is happening along the way to the Internet of Things, namely far too many devices to work with and manage. It has become clear that we'll need much higher efficiency user experiences that can allow us to more easily and scalably work with the thousands of devices that will soon be in each of our lives. Enter the conversational interface revolution, combining bots we can literally talk with, gesture to, and even direct with our thoughts, with embedded artificial intelligence, whic...
Feb. 27, 2017 06:30 PM EST Reads: 2,157
WebRTC sits at the intersection between VoIP and the Web. As such, it poses some interesting challenges for those developing services on top of it, but also for those who need to test and monitor these services. In his session at WebRTC Summit, Tsahi Levent-Levi, co-founder of testRTC, reviewed the various challenges posed by WebRTC when it comes to testing and monitoring and on ways to overcome them.
Feb. 27, 2017 06:15 PM EST Reads: 8,322
In his session at @ThingsExpo, Steve Wilkes, CTO and founder of Striim, will delve into four enterprise-scale, business-critical case studies where streaming analytics serves as the key to enabling real-time data integration and right-time insights in hybrid cloud, IoT, and fog computing environments. As part of this discussion, he will also present a demo based on its partnership with Fujitsu, highlighting their technologies in a healthcare IoT use-case. The demo showcases the tracking of patie...
Feb. 27, 2017 04:45 PM EST Reads: 1,529
In his keynote at 18th Cloud Expo, Andrew Keys, Co-Founder of ConsenSys Enterprise, provided an overview of the evolution of the Internet and the Database and the future of their combination – the Blockchain. Andrew Keys is Co-Founder of ConsenSys Enterprise. He comes to ConsenSys Enterprise with capital markets, technology and entrepreneurial experience. Previously, he worked for UBS investment bank in equities analysis. Later, he was responsible for the creation and distribution of life settle...
Feb. 27, 2017 04:45 PM EST Reads: 1,890
The explosion of new web/cloud/IoT-based applications and the data they generate are transforming our world right before our eyes. In this rush to adopt these new technologies, organizations are often ignoring fundamental questions concerning who owns the data and failing to ask for permission to conduct invasive surveillance of their customers. Organizations that are not transparent about how their systems gather data telemetry without offering shared data ownership risk product rejection, regu...
Feb. 27, 2017 03:30 PM EST Reads: 2,350
The best way to leverage your Cloud Expo presence as a sponsor and exhibitor is to plan your news announcements around our events. The press covering Cloud Expo and @ThingsExpo will have access to these releases and will amplify your news announcements. More than two dozen Cloud companies either set deals at our shows or have announced their mergers and acquisitions at Cloud Expo. Product announcements during our show provide your company with the most reach through our targeted audiences.
Feb. 27, 2017 02:45 PM EST Reads: 2,671
SYS-CON Events announced today that Cloud Academy will exhibit at SYS-CON's 20th International Cloud Expo®, which will take place on June 6-8, 2017, at the Javits Center in New York City, NY. Cloud Academy is the industry’s most innovative, vendor-neutral cloud technology training platform. Cloud Academy provides continuous learning solutions for individuals and enterprise teams for Amazon Web Services, Microsoft Azure, Google Cloud Platform, and the most popular cloud computing technologies. Ge...
Feb. 27, 2017 02:30 PM EST Reads: 2,030
20th Cloud Expo, taking place June 6-8, 2017, at the Javits Center in New York City, NY, will feature technical sessions from a rock star conference faculty and the leading industry players in the world. Cloud computing is now being embraced by a majority of enterprises of all sizes. Yesterday's debate about public vs. private has transformed into the reality of hybrid cloud: a recent survey shows that 74% of enterprises have a hybrid cloud strategy.
Feb. 27, 2017 01:45 PM EST Reads: 2,568