|By Sam Pullara||
|February 20, 2002 12:00 AM EST||
Application server performance. Database performance. Hardware performance. These are numbers measured in the popular press, although in most situations they have little to do with your application's real-world performance. The number one way to increase performance, the thing that gives you the biggest boost, is caching. Caching in every tier is becoming more and more prevalent. On the front end, we have caching proxy servers like Squid and AOL. On the back end, we have databases and file systems that are caching our data. This month, I'm going to talk about caching in the Web application layer of the middle tier, where your application meets the Internet.
In WebLogic Server 5.1, the JSP cache tag was introduced for caching in the Web application tier. This tag allows you to cache both input (values of variables) and output (typically, the generated HTML). Ideally, these tags can be used so you have what I call "exact caching." In other words, even though caching was introduced, no change in the functionality of the application was made because the data in the cache is always the same as the real data. This is similar to how caches are used on CPUs, databases, and file systems. Just because something is cached, it doesn't mean that it's out of date. This isn't the only way to architect your caching layer. It's also possible to analyze the system and find places where you'd rather have an out-of-date answer right now, rather than an up-to-date answer after blocking the user for a time.
Here's an example of "exact caching." On my Web site I built a DVD check-out service for the people who live in my loft building. At the time, I was experimenting with XML and wanted to use it to store all the information about the registered users and the DVDs. Since I was just using the file system, parsing the XML all the time was time consuming. However, since I knew when the application was updating the XML files, I could use the cache tag to store the results of the parse and only flush the cache when they changed. This led to an order-of-magnitude increase in speed, with no loss of functionality. Voila, "exact caching."
Similarly, in the first application of the cache tag in production, a customer used the tag to cache the content from their content management system. Since they could cache based on variables in the page, they were able to only query the update time of the document in question on each request, instead of pulling the whole document over to the file system each time. This also garnered them an order-of-magnitude improvement in performance for the affected operations.
Much more difficult to architect properly is timeout-based caching. This is the normal caching that your browser and proxy servers do. When you get a Web page back from a Web site, a time stamp is returned that tells you when the page might be out of date; it's stored in the "Expires" header. If you request the page before that time, your browser will first go to its local cache for the contents (unless you force it to return to the Web site). Obviously, this method assumes that all content on the page expires at the same time and that your primary concern is reducing the bandwidth load on the server. For many application server deployments, the primary concern isn't bandwidth, but reducing the load on the servers themselves. That's where caching in the middle-tier has its sweet spot. Timeout-based caches assume that the application developer has special knowledge about the time sensitivity of the data that is being used to generate the Web page. For instance, you might be offering 20-minute delayed stock quotes and you might decide that the most popular stocks should be cached so that when users request a quote they are given the same one as everyone else who asks within some specified period of time. Determining that period is the important part of the exercise. Let's say you decide that you're only going to update the cache every 5 seconds; the quotes are already 20 minutes old anyway. If you're getting 10 requests per second for a particular ticker, that means you get 50 requests in 5 seconds, so you're doing 50 times less work to get each quote minus the cache overhead! Quite a savings for very little loss in functionality.
As you can see, caching can tremendously improve the performance of your Web applications. Using cache tags and cache filters (new in 7.0), you can build very robust, performant, scalable applications with only a bit more careful investment in design and architecture. We have only touched the surface of what you can do with caches in the Web application layer in this article; you can find out much more about caching using these tools on my Web site at www.sampullara.com/caching.
|wesnur 03/24/10 05:28:00 AM EDT|
I agreed that caching is the best way to increase the performance of the app as it reduces expensive data trips to the data base by reducing the performance bottle neck. It’s the arena of distributed caching now as concept of local caching has become a bit old. You can’t achieve desired results if you have local cache especially if your data is distributed over many servers. There many distributed caching solution are available now days but NCache and MS Velocity being the most famous ones.
SYS-CON Events announced today that Dyn, the worldwide leader in Internet Performance, will exhibit at SYS-CON's 17th International Cloud Expo®, which will take place on November 3-5, 2015, at the Santa Clara Convention Center in Santa Clara, CA. Dyn is a cloud-based Internet Performance company. Dyn helps companies monitor, control, and optimize online infrastructure for an exceptional end-user experience. Through a world-class network and unrivaled, objective intelligence into Internet conditions, Dyn ensures traffic gets delivered faster, safer, and more reliably than ever.
Oct. 9, 2015 11:00 PM EDT Reads: 616
Today air travel is a minefield of delays, hassles and customer disappointment. Airlines struggle to revitalize the experience. GE and M2Mi will demonstrate practical examples of how IoT solutions are helping airlines bring back personalization, reduce trip time and improve reliability. In their session at @ThingsExpo, Shyam Varan Nath, Principal Architect with GE, and Dr. Sarah Cooper, M2Mi's VP Business Development and Engineering, will explore the IoT cloud-based platform technologies driving this change including privacy controls, data transparency and integration of real time context w...
Oct. 9, 2015 10:15 PM EDT Reads: 135
The IoT market is on track to hit $7.1 trillion in 2020. The reality is that only a handful of companies are ready for this massive demand. There are a lot of barriers, paint points, traps, and hidden roadblocks. How can we deal with these issues and challenges? The paradigm has changed. Old-style ad-hoc trial-and-error ways will certainly lead you to the dead end. What is mandatory is an overarching and adaptive approach to effectively handle the rapid changes and exponential growth.
Oct. 9, 2015 10:00 PM EDT Reads: 241
Who are you? How do you introduce yourself? Do you use a name, or do you greet a friend by the last four digits of his social security number? Assuming you don’t, why are we content to associate our identity with 10 random digits assigned by our phone company? Identity is an issue that affects everyone, but as individuals we don’t spend a lot of time thinking about it. In his session at @ThingsExpo, Ben Klang, Founder & President of Mojo Lingo, will discuss the impact of technology on identity. Should we federate, or not? How should identity be secured? Who owns the identity? How is identity ...
Oct. 9, 2015 10:00 PM EDT Reads: 452
The buzz continues for cloud, data analytics and the Internet of Things (IoT) and their collective impact across all industries. But a new conversation is emerging - how do companies use industry disruption and technology enablers to lead in markets undergoing change, uncertainty and ambiguity? Organizations of all sizes need to evolve and transform, often under massive pressure, as industry lines blur and merge and traditional business models are assaulted and turned upside down. In this new data-driven world, marketplaces reign supreme while interoperability, APIs and applications deliver un...
Oct. 9, 2015 08:00 PM EDT Reads: 316
Too often with compelling new technologies market participants become overly enamored with that attractiveness of the technology and neglect underlying business drivers. This tendency, what some call the “newest shiny object syndrome,” is understandable given that virtually all of us are heavily engaged in technology. But it is also mistaken. Without concrete business cases driving its deployment, IoT, like many other technologies before it, will fade into obscurity.
Oct. 9, 2015 07:45 PM EDT Reads: 171
Electric power utilities face relentless pressure on their financial performance, and reducing distribution grid losses is one of the last untapped opportunities to meet their business goals. Combining IoT-enabled sensors and cloud-based data analytics, utilities now are able to find, quantify and reduce losses faster – and with a smaller IT footprint. Solutions exist using Internet-enabled sensors deployed temporarily at strategic locations within the distribution grid to measure actual line loads.
Oct. 9, 2015 06:30 PM EDT Reads: 140
The Internet of Everything is re-shaping technology trends–moving away from “request/response” architecture to an “always-on” Streaming Web where data is in constant motion and secure, reliable communication is an absolute necessity. As more and more THINGS go online, the challenges that developers will need to address will only increase exponentially. In his session at @ThingsExpo, Todd Greene, Founder & CEO of PubNub, will explore the current state of IoT connectivity and review key trends and technology requirements that will drive the Internet of Things from hype to reality.
Oct. 9, 2015 05:30 PM EDT Reads: 115
The Internet of Things (IoT) is growing rapidly by extending current technologies, products and networks. By 2020, Cisco estimates there will be 50 billion connected devices. Gartner has forecast revenues of over $300 billion, just to IoT suppliers. Now is the time to figure out how you’ll make money – not just create innovative products. With hundreds of new products and companies jumping into the IoT fray every month, there’s no shortage of innovation. Despite this, McKinsey/VisionMobile data shows "less than 10 percent of IoT developers are making enough to support a reasonably sized team....
Oct. 9, 2015 04:00 PM EDT Reads: 247
You have your devices and your data, but what about the rest of your Internet of Things story? Two popular classes of technologies that nicely handle the Big Data analytics for Internet of Things are Apache Hadoop and NoSQL. Hadoop is designed for parallelizing analytical work across many servers and is ideal for the massive data volumes you create with IoT devices. NoSQL databases such as Apache HBase are ideal for storing and retrieving IoT data as “time series data.”
Oct. 9, 2015 03:45 PM EDT Reads: 510
Today’s connected world is moving from devices towards things, what this means is that by using increasingly low cost sensors embedded in devices we can create many new use cases. These span across use cases in cities, vehicles, home, offices, factories, retail environments, worksites, health, logistics, and health. These use cases rely on ubiquitous connectivity and generate massive amounts of data at scale. These technologies enable new business opportunities, ways to optimize and automate, along with new ways to engage with users.
Oct. 9, 2015 02:00 PM EDT Reads: 191
The IoT is upon us, but today’s databases, built on 30-year-old math, require multiple platforms to create a single solution. Data demands of the IoT require Big Data systems that can handle ingest, transactions and analytics concurrently adapting to varied situations as they occur, with speed at scale. In his session at @ThingsExpo, Chad Jones, chief strategy officer at Deep Information Sciences, will look differently at IoT data so enterprises can fully leverage their IoT potential. He’ll share tips on how to speed up business initiatives, harness Big Data and remain one step ahead by apply...
Oct. 9, 2015 01:45 PM EDT Reads: 565
There will be 20 billion IoT devices connected to the Internet soon. What if we could control these devices with our voice, mind, or gestures? What if we could teach these devices how to talk to each other? What if these devices could learn how to interact with us (and each other) to make our lives better? What if Jarvis was real? How can I gain these super powers? In his session at 17th Cloud Expo, Chris Matthieu, co-founder and CTO of Octoblu, will show you!
Oct. 9, 2015 01:15 PM EDT
SYS-CON Events announced today that ProfitBricks, the provider of painless cloud infrastructure, will exhibit at SYS-CON's 17th International Cloud Expo®, which will take place on November 3–5, 2015, at the Santa Clara Convention Center in Santa Clara, CA. ProfitBricks is the IaaS provider that offers a painless cloud experience for all IT users, with no learning curve. ProfitBricks boasts flexible cloud servers and networking, an integrated Data Center Designer tool for visual control over the cloud and the best price/performance value available. ProfitBricks was named one of the coolest Clo...
Oct. 9, 2015 01:00 PM EDT Reads: 804
As a company adopts a DevOps approach to software development, what are key things that both the Dev and Ops side of the business must keep in mind to ensure effective continuous delivery? In his session at DevOps Summit, Mark Hydar, Head of DevOps, Ericsson TV Platforms, will share best practices and provide helpful tips for Ops teams to adopt an open line of communication with the development side of the house to ensure success between the two sides.
Oct. 9, 2015 01:00 PM EDT Reads: 618
SYS-CON Events announced today that IBM Cloud Data Services has been named “Bronze Sponsor” of SYS-CON's 17th Cloud Expo, which will take place on November 3–5, 2015, at the Santa Clara Convention Center in Santa Clara, CA. IBM Cloud Data Services offers a portfolio of integrated, best-of-breed cloud data services for developers focused on mobile computing and analytics use cases.
Oct. 9, 2015 12:00 PM EDT Reads: 743
SYS-CON Events announced today that Sandy Carter, IBM General Manager Cloud Ecosystem and Developers, and a Social Business Evangelist, will keynote at the 17th International Cloud Expo®, which will take place on November 3–5, 2015, at the Santa Clara Convention Center in Santa Clara, CA.
Oct. 9, 2015 11:15 AM EDT
Developing software for the Internet of Things (IoT) comes with its own set of challenges. Security, privacy, and unified standards are a few key issues. In addition, each IoT product is comprised of at least three separate application components: the software embedded in the device, the backend big-data service, and the mobile application for the end user's controls. Each component is developed by a different team, using different technologies and practices, and deployed to a different stack/target - this makes the integration of these separate pipelines and the coordination of software upd...
Oct. 9, 2015 09:00 AM EDT Reads: 299
Mobile messaging has been a popular communication channel for more than 20 years. Finnish engineer Matti Makkonen invented the idea for SMS (Short Message Service) in 1984, making his vision a reality on December 3, 1992 by sending the first message ("Happy Christmas") from a PC to a cell phone. Since then, the technology has evolved immensely, from both a technology standpoint, and in our everyday uses for it. Originally used for person-to-person (P2P) communication, i.e., Sally sends a text message to Betty – mobile messaging now offers tremendous value to businesses for customer and empl...
Oct. 9, 2015 08:30 AM EDT Reads: 315
"Matrix is an ambitious open standard and implementation that's set up to break down the fragmentation problems that exist in IP messaging and VoIP communication," explained John Woolf, Technical Evangelist at Matrix, in this SYS-CON.tv interview at @ThingsExpo, held Nov 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA.
Oct. 9, 2015 07:00 AM EDT Reads: 5,892