|By Peter Velikin||
|May 2, 2012 07:00 AM EDT||
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.
ScriptRock makes GuardRail, a DevOps-ready platform for configuration monitoring. Realizing we were spending way too much time digging up, cataloguing, and tracking machine configurations, we began writing our own scripts and tools to handle what is normally an enormous chore. Then we took the concept a step further, giving it a beautiful interface and making it simple enough for our bosses to understand. We named it GuardRail after its function - to allow businesses to move fast and stay sa...
Dec. 21, 2014 02:30 PM EST Reads: 1,113
In high-production environments where release cycles are measured in hours or minutes — not days or weeks — there's little room for mistakes and no room for confusion. Everyone has to understand what's happening, in real time, and have the means to do whatever is necessary to keep applications up and running optimally. DevOps is a high-stakes world, but done well, it delivers the agility and performance to significantly impact business competitiveness.
Dec. 21, 2014 02:00 PM EST Reads: 988
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 ...
Dec. 21, 2014 02:00 PM EST Reads: 3,019
"BSQUARE is in the business of selling software solutions for smart connected devices. It's obvious that IoT has moved from being a technology to being a fundamental part of business, and in the last 18 months people have said let's figure out how to do it and let's put some focus on it, " explained Dave Wagstaff, VP & Chief Architect, at BSQUARE Corporation, in this SYS-CON.tv interview at @ThingsExpo, held Nov 4-6, 2014, at the Santa Clara Convention Center in Santa Clara, CA.
Dec. 21, 2014 01:00 PM EST Reads: 2,563
SYS-CON Media announced today that Sematext launched a popular blog feed on DevOps Journal with over 6,000 story reads over the weekend. 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. Sematext is a globally distributed organization that builds innovative Cloud and On Premises solutions for performance monitoring, alerting an...
Dec. 21, 2014 01:00 PM EST Reads: 1,083
The major cloud platforms defy a simple, side-by-side analysis. Each of the major IaaS public-cloud platforms offers their own unique strengths and functionality. Options for on-site private cloud are diverse as well, and must be designed and deployed while taking existing legacy architecture and infrastructure into account. Then the reality is that most enterprises are embarking on a hybrid cloud strategy and programs. In this Power Panel at 15th Cloud Expo (http://www.CloudComputingExpo.com...
Dec. 21, 2014 11:30 AM EST Reads: 3,116
Verizon Enterprise Solutions is simplifying the cloud-purchasing experience for its clients, with the launch of Verizon Cloud Marketplace, a key foundational component of the company's robust ecosystem of enterprise-class technologies. The online storefront will initially feature pre-built cloud-based services from AppDynamics, Hitachi Data Systems, Juniper Networks, PfSense and Tervela. Available globally to enterprises using Verizon Cloud, Verizon Cloud Marketplace provides a one-stop shop fo...
Dec. 21, 2014 11:00 AM EST Reads: 2,615
Leysin American School is an exclusive, private boarding school located in Leysin, Switzerland. Leysin selected an OpenStack-powered, private cloud as a service to manage multiple applications and provide development environments for students across the institution. Seeking to meet rigid data sovereignty and data integrity requirements while offering flexible, on-demand cloud resources to users, Leysin identified OpenStack as the clear choice to round out the school's cloud strategy. Additional...
Dec. 21, 2014 11:00 AM EST Reads: 2,753
SYS-CON Events announced today that IDenticard will exhibit at SYS-CON's 16th International Cloud Expo®, which will take place on June 9-11, 2015, at the Javits Center in New York City, NY. IDenticard™ is the security division of Brady Corp (NYSE: BRC), a $1.5 billion manufacturer of identification products. We have small-company values with the strength and stability of a major corporation. IDenticard offers local sales, support and service to our customers across the United States and Canada...
Dec. 21, 2014 10:00 AM EST Reads: 2,696
The move in recent years to cloud computing services and architectures has added significant pace to the application development and deployment environment. When enterprise IT can spin up large computing instances in just minutes, developers can also design and deploy in small time frames that were unimaginable a few years ago. The consequent move toward lean, agile, and fast development leads to the need for the development and operations sides to work very closely together. Thus, DevOps become...
Dec. 21, 2014 10:00 AM EST Reads: 2,760
SYS-CON Events announced today that Windstream, a leading provider of advanced network and cloud communications, has been named “Silver Sponsor” of SYS-CON's 16th International Cloud Expo®, which will take place on June 9–11, 2015, at the Javits Center in New York, NY. Windstream (Nasdaq: WIN), a FORTUNE 500 and S&P 500 company, is a leading provider of advanced network communications, including cloud computing and managed services, to businesses nationwide. The company also offers broadband, p...
Dec. 21, 2014 08:30 AM EST Reads: 2,909
SYS-CON Events announced today that AIC, a leading provider of OEM/ODM server and storage solutions, will exhibit at SYS-CON's 16th International Cloud Expo®, which will take place on June 9-11, 2015, at the Javits Center in New York City, NY. AIC is a leading provider of both standard OTS, off-the-shelf, and OEM/ODM server and storage solutions. With expert in-house design capabilities, validation, manufacturing and production, AIC's broad selection of products are highly flexible and are conf...
Dec. 21, 2014 06:30 AM EST Reads: 2,551
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.
Dec. 20, 2014 11:00 PM EST Reads: 2,043
SYS-CON Events announced today Isomorphic Software, the global leader in high-end, web-based business applications, will exhibit at SYS-CON's DevOps Summit 2015 New York, which will take place on June 9-11, 2015, at the Javits Center in New York City, NY. Isomorphic Software is the global leader in high-end, web-based business applications. We develop, market, and support the SmartClient & Smart GWT HTML5/Ajax platform, combining the productivity and performance of traditional desktop software ...
Dec. 20, 2014 11:00 PM EST Reads: 1,915
"Our premise is Docker is not enough. That's not a bad thing - we actually love Docker. At ActiveState all our products are based on open source technology and Docker is an up-and-coming piece of open source technology," explained Bart Copeland, President & CEO of ActiveState Software, in this SYS-CON.tv interview at DevOps Summit at Cloud Expo®, held Nov 4-6, 2014, at the Santa Clara Convention Center in Santa Clara, CA.
Dec. 20, 2014 11:00 AM EST Reads: 2,689
AppZero has announced that its award-winning application migration software is now fully qualified within the Microsoft Azure Certified program. AppZero has undergone extensive technical evaluation with Microsoft Corp., earning its designation as Microsoft Azure Certified. As a result of AppZero's work with Microsoft, customers are able to easily find, purchase and deploy AppZero from the Azure Marketplace. With just a few clicks, users have an Azure-based solution for moving applications to the...
Dec. 20, 2014 09:00 AM EST Reads: 1,657
“In the past year we've seen a lot of stabilization of WebRTC. You can now use it in production with a far greater degree of certainty. A lot of the real developments in the past year have been in things like the data channel, which will enable a whole new type of application," explained Peter Dunkley, Technical Director at Acision, in this SYS-CON.tv interview at @ThingsExpo, held Nov 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA.
Dec. 20, 2014 08:00 AM EST Reads: 2,196
The cloud is becoming the de-facto way for enterprises to leverage common infrastructure while innovating and one of the biggest obstacles facing public cloud computing is security. In his session at 15th Cloud Expo, Jeff Aliber, a global marketing executive at Verizon, discussed how the best place for web security is in the cloud. Benefits include: Functions as the first layer of defense Easy operation –CNAME change Implement an integrated solution Best architecture for addressing network-l...
Dec. 20, 2014 05:00 AM EST Reads: 2,122
“We help people build clusters, in the classical sense of the cluster. We help people put a full stack on top of every single one of those machines. We do the full bare metal install," explained Greg Bruno, Vice President of Engineering and co-founder of StackIQ, in this SYS-CON.tv interview at 15th Cloud Expo, held Nov 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA.
Dec. 19, 2014 11:45 PM EST Reads: 2,116