Click here to close now.




















Welcome!

Weblogic Authors: Elizabeth White, Michael Meiner, Michael Bushong, Avi Rosenthal

Related Topics: Weblogic

Weblogic: Article

Caching

Caching

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 Just because something is cached, it doesn't mean that it's out of date.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 It's also possible to analyze the system and find places where you'd rather have an out-of-date answer right now, rather than an up-to-date answer after blocking the user for a time.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.

More Stories By Sam Pullara

Sam Pullara has been a software engineer at WebLogic since 1996 and has contributed to the architecture, design, and implementation of many aspects of the application server.

e-mail: [email protected]

Comments (1) View Comments

Share your thoughts on this story.

Add your comment
You must be signed in to add a comment. Sign-in | Register

In accordance with our Comment Policy, we encourage comments that are on topic, relevant and to-the-point. We will remove comments that include profanity, personal attacks, racial slurs, threats of violence, or other inappropriate material that violates our Terms and Conditions, and will block users who make repeated violations. We ask all readers to expect diversity of opinion and to treat one another with dignity and respect.


Most Recent Comments
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.

@ThingsExpo Stories
SYS-CON Events announced today that IceWarp will exhibit 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. IceWarp, the leader of cloud and on-premise messaging, delivers secured email, chat, documents, conferencing and collaboration to today's mobile workforce, all in one unified interface
In his session at @ThingsExpo, Lee Williams, a producer of the first smartphones and tablets, will talk about how he is now applying his experience in mobile technology to the design and development of the next generation of Environmental and Sustainability Services at ETwater. He will explain how M2M controllers work through wirelessly connected remote controls; and specifically delve into a retrofit option that reverse-engineers control codes of existing conventional controller systems so they don't have to be replaced and are instantly converted to become smart, connected devices.
The Internet of Things is in the early stages of mainstream deployment but it promises to unlock value and rapidly transform how organizations manage, operationalize, and monetize their assets. IoT is a complex structure of hardware, sensors, applications, analytics and devices that need to be able to communicate geographically and across all functions. Once the data is collected from numerous endpoints, the challenge then becomes converting it into actionable insight.
With the proliferation of connected devices underpinning new Internet of Things systems, Brandon Schulz, Director of Luxoft IoT – Retail, will be looking at the transformation of the retail customer experience in brick and mortar stores in his session at @ThingsExpo. Questions he will address include: Will beacons drop to the wayside like QR codes, or be a proximity-based profit driver? How will the customer experience change in stores of all types when everything can be instrumented and analyzed? As an area of investment, how might a retail company move towards an innovation methodolo...
SYS-CON Events announced today that HPM Networks will exhibit 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. For 20 years, HPM Networks has been integrating technology solutions that solve complex business challenges. HPM Networks has designed solutions for both SMB and enterprise customers throughout the San Francisco Bay Area.
Consumer IoT applications provide data about the user that just doesn’t exist in traditional PC or mobile web applications. This rich data, or “context,” enables the highly personalized consumer experiences that characterize many consumer IoT apps. This same data is also providing brands with unprecedented insight into how their connected products are being used, while, at the same time, powering highly targeted engagement and marketing opportunities. In his session at @ThingsExpo, Nathan Treloar, President and COO of Bebaio, will explore examples of brands transforming their businesses by t...
Through WebRTC, audio and video communications are being embedded more easily than ever into applications, helping carriers, enterprises and independent software vendors deliver greater functionality to their end users. With today’s business world increasingly focused on outcomes, users’ growing calls for ease of use, and businesses craving smarter, tighter integration, what’s the next step in delivering a richer, more immersive experience? That richer, more fully integrated experience comes about through a Communications Platform as a Service which allows for messaging, screen sharing, video...
SYS-CON Events announced today that Pythian, a global IT services company specializing in helping companies leverage disruptive technologies to optimize revenue-generating systems, 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. Founded in 1997, Pythian is a global IT services company that helps companies compete by adopting disruptive technologies such as cloud, Big Data, advanced analytics, and DevOps to advance innovation and increase agility. Specializing in designing, imple...
As more and more data is generated from a variety of connected devices, the need to get insights from this data and predict future behavior and trends is increasingly essential for businesses. Real-time stream processing is needed in a variety of different industries such as Manufacturing, Oil and Gas, Automobile, Finance, Online Retail, Smart Grids, and Healthcare. Azure Stream Analytics is a fully managed distributed stream computation service that provides low latency, scalable processing of streaming data in the cloud with an enterprise grade SLA. It features built-in integration with Azur...
SYS-CON Events announced today that Micron Technology, Inc., a global leader in advanced semiconductor systems, will exhibit 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. Micron’s broad portfolio of high-performance memory technologies – including DRAM, NAND and NOR Flash – is the basis for solid state drives, modules, multichip packages and other system solutions. Backed by more than 35 years of technology leadership, Micron's memory solutions enable the world's most innovative computing, consumer,...
Contrary to mainstream media attention, the multiple possibilities of how consumer IoT will transform our everyday lives aren’t the only angle of this headline-gaining trend. There’s a huge opportunity for “industrial IoT” and “Smart Cities” to impact the world in the same capacity – especially during critical situations. For example, a community water dam that needs to release water can leverage embedded critical communications logic to alert the appropriate individuals, on the right device, as soon as they are needed to take action.
With the Apple Watch making its way onto wrists all over the world, it’s only a matter of time before it becomes a staple in the workplace. In fact, Forrester reported that 68 percent of technology and business decision-makers characterize wearables as a top priority for 2015. Recognizing their business value early on, FinancialForce.com was the first to bring ERP to wearables, helping streamline communication across front and back office functions. In his session at @ThingsExpo, Kevin Roberts, GM of Platform at FinancialForce.com, will discuss the value of business applications on wearable ...
As more intelligent IoT applications shift into gear, they’re merging into the ever-increasing traffic flow of the Internet. It won’t be long before we experience bottlenecks, as IoT traffic peaks during rush hours. Organizations that are unprepared will find themselves by the side of the road unable to cross back into the fast lane. As billions of new devices begin to communicate and exchange data – will your infrastructure be scalable enough to handle this new interconnected world?
While many app developers are comfortable building apps for the smartphone, there is a whole new world out there. In his session at @ThingsExpo, Narayan Sainaney, Co-founder and CTO of Mojio, will discuss how the business case for connected car apps is growing and, with open platform companies having already done the heavy lifting, there really is no barrier to entry.
WebRTC has had a real tough three or four years, and so have those working with it. Only a few short years ago, the development world were excited about WebRTC and proclaiming how awesome it was. You might have played with the technology a couple of years ago, only to find the extra infrastructure requirements were painful to implement and poorly documented. This probably left a bitter taste in your mouth, especially when things went wrong.
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.
The Internet of Things (IoT) is about the digitization of physical assets including sensors, devices, machines, gateways, and the network. It creates possibilities for significant value creation and new revenue generating business models via data democratization and ubiquitous analytics across IoT networks. The explosion of data in all forms in IoT requires a more robust and broader lens in order to enable smarter timely actions and better outcomes. Business operations become the key driver of IoT applications and projects. Business operations, IT, and data scientists need advanced analytics t...
Akana has announced the availability of the new Akana Healthcare Solution. The API-driven solution helps healthcare organizations accelerate their transition to being secure, digitally interoperable businesses. It leverages the Health Level Seven International Fast Healthcare Interoperability Resources (HL7 FHIR) standard to enable broader business use of medical data. Akana developed the Healthcare Solution in response to healthcare businesses that want to increase electronic, multi-device access to health records while reducing operating costs and complying with government regulations.
For IoT to grow as quickly as analyst firms’ project, a lot is going to fall on developers to quickly bring applications to market. But the lack of a standard development platform threatens to slow growth and make application development more time consuming and costly, much like we’ve seen in the mobile space. In his session at @ThingsExpo, Mike Weiner, Product Manager of the Omega DevCloud with KORE Telematics Inc., discussed the evolving requirements for developers as IoT matures and conducted a live demonstration of how quickly application development can happen when the need to comply wit...
The Internet of Everything (IoE) brings together people, process, data and things to make networked connections more relevant and valuable than ever before – transforming information into knowledge and knowledge into wisdom. IoE creates new capabilities, richer experiences, and unprecedented opportunities to improve business and government operations, decision making and mission support capabilities.