Click here to close now.

Welcome!

AJAX & REA Authors: David Miller, AppDynamics Blog, Pat Romanski, Liz McMillan, Mike Kavis

Related Topics: Virtualization, Microservices Journal, Open Source

Virtualization: Blog Feed Post

Using RAM in SSD Caching

Dr Dog Says “You Need More RAM In Your Cache Diet”

Dr Dog Says “You Need More RAM In Your Cache Diet”
Well, I am not really a doctor, but I play one on TV. You may remember (if you are old enough) that line from the 1986 Vicks-44 TV commercial.  Anyway, while I may not be a real doctor, I can certainly tell you about why you need more RAM in you cache diet.

“I Think My Cache Diet Is Great”
If you were happily running your IT system but needed some additional performance, chances are you turned to some kind of SSD caching solution to improve performance at a lower cost point than adding more servers or storage. You went on what I am calling a “cache diet” (no, not the “crash diet” you went on last year to lose a few lbs).  You may think your cache diet is great.  “Dog, we got some performance improvement and the applications guys are not bothering me anymore, at least for now.”  And it is true, you did see some performance improvement when you went to an SSD caching solution….but now, things are starting to slow down again and the applications guys are making noise again. You are experiencing IO bottlenecks and higher latency times for data access or you just never really got all the improvements you expected. “So what do I do now, Dr. Dog?”  Well, the problem is the SSD cache solution you implemented does not have any RAM in it and the solution from the good doctor is “you need more RAM in your cache diet.”

We Call It “Hybrid Caching”
SSD caching is a combination of an SSD device and SSD caching software.  It is being sold by many vendors and comes in many flavors.   It can be installed in many different locations in the computer system storage architecture.  This was discussed in a recently posted blog where the pros/cons of each location were discussed.  What was not talked about in that blog, however, was what types of caching algorithms actually used RAM as part of their solution.  At Velobit, we use a combination of SSD and RAM to implement our SSD caching software; a solution we refer to as “hybrid caching.”

“So What Does More RAM In My Cache Diet Actually Do?”
“Doctor” Dog shall explain: Using RAM with SSD cache hardware makes the life of the SSD better.  Even a small amount of RAM is effective in reducing IO loads on the SSD.  Obviously, if RAM is used for cache, a RAM cache hit is going to respond faster than any SSD and frees the SSD to perform other essential tasks such as garbage collection and complete pending writes.  SSDs perform poorly with mixed read/write IOs. A RAM cache helps limit mixed writes/reads, improving SSD performance and overall cache performance.

Velobit HyperCache SSD caching software uses RAM efficiently so even a small amount of RAM allocated to caching can impact performance.  Velobit uses compression algorithms based on content locality caching to reduce the amount of physical data stored in RAM.  The impact of this is to effectively increase the virtual cache size without dedicating excessive RAM resources to cache. And, while some file system caching software can use RAM to improve performance, those techniques do not use data compression to maximize the performance of the allocated RAM.

Finally, using RAM in the caching algorithm allows the Velobit SSD caching software to do selective SSD writes – it does not write data to the SSD unless the data needs to go there.  Sequential data is written directly to HDD, completely bypassing the SSD.

“I Feel Better Already”
So, if your SSD caching system seems a little, shall we say, constipated, you can probably fix that by adding a little RAM to your SSD cache diet.

Read the original blog entry...

More Stories By Peter Velikin

Peter Velikin has 12 years of experience creating new markets and commercializing products in multiple high tech industries. Prior to VeloBit, he was VP Marketing at Zmags, a SaaS-based digital content platform for e-commerce and mobile devices, where he managed all aspects of marketing, product management, and business development. Prior to that, Peter was Director of Product and Market Strategy at PTC, responsible for PTC’s publishing, content management, and services solutions. Prior to PTC, Peter was at EMC Corporation, where he held roles in product management, business development, and engineering program management.

Peter has an MS in Electrical Engineering from Boston University and an MBA from Harvard Business School.

@CloudExpo Stories
SYS-CON Media named Andi Mann editor of DevOps Journal. DevOps Journal is focused on this critical enterprise IT topic in the world of cloud computing. DevOps Journal brings valuable information to DevOps professionals who are transforming the way enterprise IT is done. Andi Mann, Vice President, Strategic Solutions, at CA Technologies, is an accomplished digital business executive with extensive global expertise as a strategist, technologist, innovator, marketer, communicator, and thought lea...
Even though it’s now Microservices Journal, long-time fans of SOA World Magazine can take comfort in the fact that the URL – soa.sys-con.com – remains unchanged. And that’s no mistake, as microservices are really nothing more than a new and improved take on the Service-Oriented Architecture (SOA) best practices we struggled to hammer out over the last decade. Skeptics, however, might say that this change is nothing more than an exercise in buzzword-hopping. SOA is passé, and now that people are ...
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. Acco...
Gartner predicts that the bulk of new IT spending by 2016 will be for cloud platforms and applications and that nearly half of large enterprises will have cloud deployments by the end of 2017. The benefits of the cloud may be clear for applications that can tolerate brief periods of downtime, but for critical applications like SQL Server, Oracle and SAP, companies need a strategy for HA and DR protection. While traditional SAN-based clusters are not possible in these environments, SANless cluste...
You often hear the two titles of "DevOps" and "Immutable Infrastructure" used independently. In his session at DevOps Summit, John Willis, Technical Evangelist for Docker, will cover the union between the two topics and why this is important. He will cover an overview of Immutable Infrastructure then show how an Immutable Continuous Delivery pipeline can be applied as a best practice for "DevOps." He will end the session with some interesting case study examples.
There is little doubt that Big Data solutions will have an increasing role in the Enterprise IT mainstream over time. 8th International Big Data Expo, co-located with 17th International Cloud Expo - to be held November 3-5, 2015, at the Santa Clara Convention Center in Santa Clara, CA - has announced its Call for Papers is open. As advanced data storage, access and analytics technologies aimed at handling high-volume and/or fast moving data all move center stage, aided by the cloud computing bo...
The 5th International DevOps Summit, co-located with 17th International Cloud Expo – being held November 3-5, 2015, at the Santa Clara Convention Center in Santa Clara, CA – announces that its Call for Papers is open. Born out of proven success in agile development, cloud computing, and process automation, DevOps is a macro trend you cannot afford to miss. From showcase success stories from early adopters and web-scale businesses, DevOps is expanding to organizations of all sizes, including the...
Enterprises are fast realizing the importance of integrating SaaS/Cloud applications, API and on-premises data and processes, to unleash hidden value. This webinar explores how managers can use a Microservice-centric approach to aggressively tackle the unexpected new integration challenges posed by proliferation of cloud, mobile, social and big data projects. Industry analyst and SOA expert Jason Bloomberg will strip away the hype from microservices, and clearly identify their advantages and d...
The time is ripe for high speed resilient software defined storage solutions with unlimited scalability. ISS has been working with the leading open source projects and developed a commercial high performance solution that is able to grow forever without performance limitations. In his session at DevOps Summit, Alex Gorbachev, President of Intelligent Systems Services Inc., will share foundation principles of Ceph architecture, as well as the design to deliver this storage to traditional SAN st...
Since 2008 and for the first time in history, more than half of humans live in urban areas, urging cities to become “smart.” Today, cities can leverage the wide availability of smartphones combined with new technologies such as Beacons or NFC to connect their urban furniture and environment to create citizen-first services that improve transportation, way-finding and information delivery. In her session at @ThingsExpo, Laetitia Gazel-Anthoine, CEO of Connecthings, will focus on successful use c...
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.
In their general session at 16th Cloud Expo, Michael Piccininni, Global Account Manager – Cloud SP at EMC Corporation, and Mike Dietze, Regional Director at Windstream Hosted Solutions, will review next generation cloud services, including the Windstream-EMC Tier Storage solutions, and discuss how to increase efficiencies, improve service delivery and enhance corporate cloud solution development. Speaker Bios Michael Piccininni is Global Account Manager – Cloud SP at EMC Corporation. He has b...
There are 182 billion emails sent every day, generating a lot of data about how recipients and ISPs respond. Many marketers take a more-is-better approach to stats, preferring to have the ability to slice and dice their email lists based numerous arbitrary stats. However, fundamentally what really matters is whether or not sending an email to a particular recipient will generate value. Data Scientists can design high-level insights such as engagement prediction models and content clusters that a...
Big Data is amazing, it's life changing and yes it is changing how we see our world. Big Data, however, can sometimes be too big. Organizations that are not amassing massive amounts of information and feeding into their decision buckets, smaller data that feeds in from customer buying patterns, buying decisions and buying influences can be more useful when used in the right way. In their session at Big Data Expo, Ermanno Bonifazi, CEO & Founder of Solgenia, and Ian Khan, Global Strategic Positi...
"We have developers who are really passionate about getting their code out to customers, no matter what, in the shortest possible time. Operations are very focused on procedures and policies," explained Stan Klimoff, CTO of Qubell, in this SYS-CON.tv interview at DevOps Summit, held Nov 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA.
DevOps Summit, taking place Nov 3-5, 2015, at the Santa Clara Convention Center in Santa Clara, CA, is co-located with 17th Cloud Expo and will feature technical sessions from a rock star conference faculty and the leading industry players in the world. 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 developmen...
It's time to face reality: "Americans are from Mars, Europeans are from Venus," and in today's increasingly connected world, understanding "inter-planetary" alignments and deviations is mission-critical for cloud. In her session at 15th Cloud Expo, Evelyn de Souza, Data Privacy and Compliance Strategy Leader at Cisco Systems, discussed cultural expectations of privacy based on new research across these elements
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 ...
Agility is top of mind for Cloud/Service providers and Enterprises alike. Policy Driven Data Center provides a policy model for application deployment by decoupling application needs from the underlying infrastructure primitives. In his session at 15th Cloud Expo, David Klebanov, a Technical Solutions Architect with Cisco Systems, discussed how it differentiates from the software-defined top-down control by offering a declarative approach to allow faster and simpler application deployment. Davi...
Sematext is a globally distributed organization that builds innovative Cloud and On Premises solutions for performance monitoring, alerting and anomaly detection (SPM), log management and analytics (Logsene), and search analytics (SSA). We also provide Search and Big Data consulting services and offer 24/7 production support for Solr and Elasticsearch.