In-Depth
5 Best Practices for Web Application Performance and Accessibility
More data means heavier workloads for servers and networks. These five tips can help you stay ahead of performance issues.
By Peter Melerud, Co-founder and Vice President of Product Development, Kemp Technologies
We're all familiar with Moore's Law that states the numbers of transistors on a chip will double every two years. So far, this prediction has been right, and as the processing power doubles, the data that our computers must handle increases exponentially. Industry research firm IDC recently estimated that the total amount of data is about 800 exabytes. To put that in perspective, that's the equivalent of 6 million Libraries of Congress -- and that number increases 62 percent each year!
Imagine the challenge we face in the future of having all of that data going through all of our computers and servers. We may not think about it much, but our data centers come dangerously close to being unable to handle the current high traffic volumes on a daily basis and will only continue to do so.
Server outages are even more costly than they are annoying in any vertical, from e-commerce to education to government. Data centers in each of these markets often must process high loads, potentially slowing them to the point of failure, and workloads will increase as data applications and video become more prevalent. Do your IT managers and data centers have the resources they need to deal with heavy traffic volume?
As with anything, preparation is key.
For example, think of this past holiday season. More than $1 billion worth of sales occurred on Cyber Monday 2010 (an all-time high, according to comScore), and hundreds of millions more transactions passed across the Web throughout the month of December. Although we heard no report of a mass outage from a major retailer, how costly would it have been if a retailer's site crashed due to cripplingly high data traffic?
Of course, most big companies have an easy solution to handling high traffic: buy additional (and more powerful) servers. However, not every business has the cavernous budget with which to purchase such expensive equipment, and this is not always the best strategy when some servers aren't constantly in use or when heavy traffic is not properly directed to the best-performing server. For small and mid-size enterprises in particular, IT money is tight; IT managers must maximize their investments to make sure users are productive and that their Web site performance meets service-level agreements.
The following best practices can help you maintain high performance and accessibility for your Web-enabled applications in tough economic times:
Best Practice #1: Know What Your Systems Can Handle
Have your servers tested to make sure they're able to handle heavy traffic. Find out if your system can cope with sudden spikes and high application usage, and compare your test results to projections for your peak usage -- and leave plenty of room for error.
Also, know what your biggest potential threats to uptime are, and know what time of the day, week, month, and year are your busiest for data traffic. If you are a hosting provider, knowing when the largest volumes of data come in from certain clients will help you plan how much of your resources will be dedicated to those clients. Having this information can go a long way toward helping to figure out when and where to place resources.
Remember: the more you know, the better prepared you are to deal with the unknown.
Best Practice #2: Keep Your Balance
Load balancers and application delivery controllers (ADCs) are solid answers to the problems of ensuring high availability and speed of access. These devices can monitor heavy traffic loads on busy servers and re-route the data to servers with less traffic, preventing crashes and keeping traffic flowing. Many ADCs are equipped with added features, such as cookie persistence and SSL acceleration, that can further enable the control and management of traffic crossing your system, particularly if hosted applications are running. If a business does not have the budget to add to its server farm, then ADCs are the most cost-effective way to maintain high performance and availability.
Best Practice #3: Persist and Succeed
Cookie persistence is a key factor in keeping your site's visitors happy. For example, online shoppers whose shopping carts suddenly disappear because, unbeknownst to them, their session got re-routed to a different server won't be happy. ADCs residing at Layer 7 are able to recognize returning users and route them back to the same server on which their information is stored -- saving them time and frustration, and potentially saving you money.
Best Practice #4: Accelerate Yourself
Another beneficial feature of ADCs is SSL acceleration. Rather than putting the burden of SSL transactions on the server and slowing server performance, an ADC can take on that security burden, freeing the server to do its regular job of transferring data and processing application requests instead of becoming an encryption processing bottleneck. The secured site loads more quickly for the user, and the experience is seamless.
Best Practice #5: Scale the Walls
New application development is essential to keep innovation at its peak. It can also be a great chance to increase revenue or at least keep customers on your site based on new opportunities to make a sale. With great developer talent, you can obtain the development you need. However, developers don't design their applications with the maximum number of users in mind, so you have to make sure any new application is scaled properly for the time when all those users click the "Submit" button simultaneously. Addressing this problem before the application goes "live" will save you -- and your users -- future headaches.
A Final Word
If you dodged the data bullet so far, consider yourself lucky. As time, technology, and market forces progress and we collect, store, and access more data, servers will be asked to take on more tasks and heavier data loads. Combined with the ever-increasing volume of data moving through networks daily, and we will have to find creative ways to stay ahead of the curve. By planning for your traffic needs and mitigating weaknesses in your data centers, you can keep data flowing for years to come.
Peter Melerud is the cofounder and vice president of product development for Kemp Technologies. You can contact the author at [email protected]