Philip Tellis at NY Web Performance, September 15

New York Web Performance Group LogoSummer is over, we’re all vacation-recharged and it’s time for some serious Web Performance! Come out of your sleepy summer mood and join us for next New York Web Performance session.

September 15 at 5:45PM (time is updated) at Logicworks:

RSVP here:

Philip Tellis (@bluesmoon) will be speaking at New York Web Performance group about Boomerang!

Philip is a self described geek working for Yahoo! who recently presented Latency: Why You Should Worry and What You Can Do About It (video) at Velocity 2010.

His accomplishments include, but not limited to:

Philip will be presenting his new open source project Boomerang.js. Why it was written, how to implement it, and what can be done with the data.

For a little background on Boomerang.js:
Boomerang is a piece of JavaScript that you add to your web pages, where it measures the performance of your website from your end user’s point of view. It has the ability to send this data back to your server for further analysis. With boomerang, you find out exactly how fast your users think your site is.< This is an excellent example of RUM (real user monitoring) that allows sites to effectively and actively measure real page performance for their actual users as they see it. Boomerang is open source and released under the BSD license. Agenda: (time is updated)
5:45 – arrive to the event, meet other members
6:00 – Introductions & Boomerang presentation by Philip Tellis
6:45 – Q&A
7:00 – Open Discussion, Networking

155 Avenue of the Americas
Fifth Floor
New York, NY 10013

Entrance View:

See you all there!

Drop-in .htaccess is now on Github. Go fork it!

Fork me on GitHubA few people got interested in drop-in web performance .htaccess file so I decided to move it to a separate project on Github and invite all of you to participate in building a simple solution for web site performance that anyone can use!

Go, fork it! We have a lot of work to do:

Check out the issue tracker, add your own suggestions / bug reports and vote for those that you think are important.

P.S. If you’d like to include sample .htaccess file with your Subversion project, just run

svn propedit svn:externals .

and add following line to it:


I did this in SVN Assets.

Meet for SPEED – hands on web performance sessions!

Time for some serious speeding up for our web sites!
Come join us at Meet for SPEED event at Logicworks next Tuesday, August 24th at 7:00PM!


Bring your laptop and we’ll work together on optimizing our sites!

You can benefit even if you can’t edit your site right now – we will be happy to share the knowledge.

We’ll all learn how to see what’s slow and how to make it fast!

155 Avenue of the Americas
Fifth Floor
New York, NY 10013

Hope to see you all there!

dynaTrace AJAX Edition at Time Inc. next week

New York Web Performance Group Logo
A special guest, Andreas Grabner is coming to New York City to present new features of upcoming dynaTrace AJAX Edition 2.0 at NY Web Performance Meetup!

dynaTrace AJAX Edition is a free tool that provides full JavaScript, Network, Rendering, DOM and XHR tracing for Internet Explorer 6, 7 & 8. With the latest version the Ajax Edition automatically analysis Best Practices in the areas of Browser Caching, Network Resources, Server-Side Activity, JavaScript/AJAX and also provides additional Key Performance Metrics that are essential for tracking the end-user perceived performance of a web site such as Time to First Impression, Time to onLoad or Time to Fully Loaded.

6:00 – arrive to the event, meet other members
6:30 – intro to web performance, industry updates by Sergey Chernyshev
7:15 – dynaTrace AJAX Edition presentation by Andreas Grabner
8:30 – Q&A
9:00 – Open Discussion, Networking

Time Inc. offered their Watercooler meeting to host NY Web Performance meetup.  Refreshments will be served.

Host contact: Alla Gringaus, Web Technology Fellow
Questions: 646 391 9671

Rockefeller Center
Time & Life Bldg
1271 Ave of the Americas (entrance 50th St and 6th Ave)
2nd Floor, room #1
New York, NY 10020

Nearest Transit:
50th St – 8th Ave (C, E)
50th St – Ave of the Americas (F, V, B, D)
49th St – 7th Ave (N, R, W)

Get directions on Google Maps:
Street View for the Entrance:

Come join us for a great presentation and discussion!

Please RSVP on the group page @

SLO-JS and how to speed up widgets

This Thursday I gave a talk at NY Web Performance about third-party content and topic proven to be quite hot with many people in the audience, good Q&A and group discussion afterwards. We talked about ad banners, widgets and tracking “pixels” and overall theme was lack of control and heavy reliance on 3rd parties.

Ads and tracking pixels, unfortunately are quite complex and changing their behavior is hard, but widgets are a bit simpler to deal with and can probably be improved.

Working on my project, I saw quite a few widgets and over time I started to realize that sales people’s magical promise of “easy integration with single line of JavaScript” which you can see on any site that provides widgets (and especially those that rely on widgets as primary method of distribution) is fundamentally flawed.

While it’s a great sales promise and simplifies integration, maintenance and gives a lot of control over user’s information, it brings slowness and introduces SPOFs to publisher’s sites.

To make people think about performance when they hear the magical sales pitch of Single line of JavaScript, I decided to abbreviate it to SLO-JS which gives a very clear impression about the performance quality of this solution.

Now, next time when you see the magical words in vendor’s proposal, there is no need to explain or complain, just abbreviate it and this will hopefully give the right impression and make people think about testing the performance of the 3rd party source.


It would’ve been pointless if there was no alternative to the SLO-JS, but in reality, it is not the only way to include code, it’s just the oldest and there are other, more reliable and fast alternatives. All we need to do is to explain how they work and make it easy for vendors to provide these alternatives to sites that care about performance.

First alternative is quite simple – instead of copy-pasting a SLO-JS snippet, just let people copy-paste a mix of HTML, CSS (optional) and async JS call that will create a reasonable placeholder until data is loaded and will not block the rendering for the rest of the site.

A few vendors are already do that – DISQUS, for example, provides the following code:

<div id="disqus_thread"></div>
<script type="text/javascript">
  (function() {
   var dsq = document.createElement('script');
   dsq.type = 'text/javascript'; dsq.async = true;
   dsq.src = '';
      || document.getElementsByTagName('body')[0])

Notice that it gives you a div tag with disqus_thread id to insert into your page (in this case the placeholder is just empty) and then uses asynchronous script tag to load the data without blocking the rest of the page.

Transforming your code to take advantage of this probably requires a couple hours of work at best – just replace document.write with static HTML wrapper (with specific ID or class) and build additional DOM elements within the code, then use wrapper’s ID to insert the DOM tree and use the async tag to load all your JS code.

Use this pattern for good widget development, suggest similar approach to vendors that give you the most grief, and we’ll have faster web pages pretty soon.

Another alternative I proposed at the Meetup is to download content on the back-end and insert it right into HTML with optional JavaScript used only for data load.

Most of the time content doesn’t change for each request and can be cached for minutes, hours or even days at a time. In some cases it never changes, especially for embeddable content like YouTube videos or Flickr photos.

Andrew Schaaf proposed a name for it – Fetch and store JavaScript with great “superhero” abbreviation of FAST-JS.

It is quite easy to implement them in the language of your choice and probably worthy of Open Source project that will enable appropriate caching mechanism and make it easy for people to implement fast solutions to SLO-JS.

It’s a bit harder to do then async widgets and requires some backend coding, but will allow reducing front-end complexity and amount of extra JS on the page to zero.