Tag Archives: web performance

Query Profiling – What is it and why is it important?

Queries are so-named because of the lovely language we call SQL – simplified query language.  That’s a bit of sarcasm on my part, I’ve never found it particularly simple or elegant.  Profiling them involves finding how they are spending their time, and what they are asking the server to do.   In this way you can make them faster, and improve performance of the whole server, and thus your website.

At any rate queries ask the database for information.  If they are on the simpler side, something like give me all the users whose name starts with “hu” for example, and last name is indexed, that will run very fast.  The database will lookup in the index the last name field, and find the subset of ones starting with those letters, then go lookup the records by id and return them to you.  Cache the index blocks, cache the data blocks.  Great!  However, say those are customers, and you want their calling cellphone calling history.  Ok, now you have to join on another table, matching by some key, hold all those records in memory, shuffle them around, and so on.

So queries are effectively little jobs or bits of work you ask your database server to perform on your behalf.  With websites you typically have hundreds of concurrently running sessions all sending their own little SQL jobs to the server to get processed, and records returned.  And blip in the radar slows everyone down, so you want them to all run quickly.

That’s where profiling comes in.  MySQL, Oracle, and SQL Server alike all have EXPLAIN type facilities for showing the plan with which the database will use to fetch your data.  It shows indexes, sorting, joins, order, and so forth.  All of this contributes to the overall execution time and resources used on the database server.

Quora discussion by Sean Hull – What is query profiling and why is it important?

Seasonal Traffic Variations – What is it and why is it important?

We applications and websites get measurable traffic, recorded in metrics such as pageviews, unique visitors, and visits.  All of this activity translates to hits to a webserver, and work for a database to retrieve information for those pages.

During one month your application might get 150,000 visits, then during one week where a large ad campaign hits, or some marketing feature goes viral, you suddenly get 500,000 visits in one week!  This is a “good problem to have” on the business side, but poses great challenges to an infrastructure as it represents a 7x increase.  What’s more if you do your capacity planning around that peak, you’ll have in 600% of your computing power and servers sitting around idle most of the year (assuming that’s just a blip).

Therein lies the challenge of seasonal traffic variations.  Capacity planning attempts to watch for trends in traffic, and growth over time of your user base.  But large spikes like the one described above can often be difficult to predict.  The whim of the masses.

Sean Hull asks on Quora – What are seasonal traffic variations and why are they important?

Web Cornerstone – iHeavy Insights Newsletter 80

I’ve recently been doing a lot of Search Engine Optimization for my corporate website.  This makes your site more visible and keyword rich for the search engines, helping your customers more easily find you. In that process it quickly becomes clear how important the website is to your business.  On the internet it is surely the cornerstone of your business, your virtual storefront.

Site Speed Is Key

Study after study from Google and others have shown that the speed and response of a website directly affects user experience and in turn use of your product or service.  It translates directly to the business bottom line.

Speed is accomplished by first measuring current speed and performance, then tuning and optimizing the various layers of technology which support it.  Then measuring again to determine the speedup.  You can then tie those changes to customer retention, higher click through rates, more time spent on the site, and higher conversions.  Apply a dollar value to your conversions and you can then estimate the direct value of that effort.

Interface to Customers

The image your company projects is formed first by your website.  The usability and simplicity affects how customers feel about interacting with your products and services.  What’s more the information, solutions, tools and downloads available also reflect directly on your business.

Analytics tools like Google’s or Yahoo’s allow you to track conversions.  These are important metrics to show when customers are taking action.  They are traditionally used for when a purchase is made on an ecommerce site, but can just as easily be put to useful work tracking bookmarks, form submissions, phone call or request a callback, downloads, newsletter signups, likes and a lot more.  If you do use conversions for these diverse functions, be sure to assign a dollar value by estimating based on the percentage who convert and those who later become paying customers in one way or another.

It’s All About Operations

Your website should be backed by a solid and flexible content management system so you can make SEO and ongoing process as well as tuning and optimization.  WordPress, Drupal, Joomla are just a few.  Use caching at every layer, and optimize images for faster download.  Of course you’ll also need to apply best practices for disaster recovery, making sure your database and content are backed up regularly, as well as your server configuration components.

All of this boils down to web operations, that hidden support providing your internet technology foundation.

Book Review: The Art of SEO by Enge, Spencer, Fishkin & Stricchiola

Search Engine Optimization is for sure one part art, but it is certainly a lot of science too, and this book really covers all of the angles.  Even if you don’t plan to do the SEO yourself, it’s good to have a strong grounding in the material so you can make intelligent decisions.

Plan to do research and brainstorm on the main keywords your customers use, what your competitors do differently and tune your site and CMS to best fit those searches.  You’ll learn to optimize title tags, content and anchor text to be keyword rich, and most importantly of all plan a link building campaign to grow inbound links to your site and thus your authority and reputation on the internet.

Art of SEO is comprehensive, easy to follow & thorough, but also easy enough to dip into here and there for pointers if that’s all you need.  I also like O’Reilly’s layouts and font, so it’s very easy on the eyes.