Welcome!

Eclipse Authors: Pat Romanski, Elizabeth White, Liz McMillan, David H Deans, JP Morgenthal

Blog Feed Post

Page Speed v1.0 VS YSlow v2.0

Last week Google announced a new open source plug-in for Firefox called Page Speed which can be used to assess the performance of web pages and make recommendations on speeding up the delivery.  To me this sounded a lot like Yslow, of course that plug-in was developed and maintained by Yahoo! so it does make sense that Google would want to come up with their own version.  As I hadn't yet upgraded to YSlow 2.0 I figured this was a good time to see what the new version had to offer and how Page Speed compares. All testing was conducted on the DevCentral home page with a unpopulated cache.

The first problem I encountered with both is that I currently am using Firefox 3.5 beta and Firebug 1.4 neither of the two add-ons currently provide support for these beta releases.  This meant reverting back to Firefox 3.0 and Firebug 1.3.3.  The next incompatibility I found was with Page Speed and HttpWatch.  These two add-ons are considered incompatible when it comes to the Page Speed Activity tab. 

 

imageThe warning message is rather vague and not to be deterred I went ahead and tested what would happen if I imageran the two together.   I was able to run both the Page Speed Activity report and HttpWatch at the same however the resulting graphs from Page Speed were illegible.  The two add-ons when run at the same time provided different response time results Page Speed said the page took 16 seconds while HttpWatch showed only 14.4 seconds.

YSlow on the other hand does not present any incompatibility warning message and the response time results are quite similar 12. 735 seconds for HttpWatch and 12.744 seconds for YSlow.  

 

 

On of the nicest new features of YSlow 2.0 is the ability to customize the rules that are applied.  There are 3 default rulesets YSlow (v2), Classic, and Small Site or Blog.  The Classic ruleset provides 13 rules while version 2 has added 9 additional rules.  I'm a little confused by the Small Site or Blog option as some of the rules that have been de-selected like using an expires header should apply to any site.  Any  of the default rule sets can be customized to add or remove a rule, for example with DevCentral we get an F for use a eContent Delivery Network (CDN) because YSlow doesn't pick up the fact that we have built our own mini-CDN with acceleration solutions from F5 Networks

Now onto some of the recommendations that are provided. 

Browser Caching

For repeat visitors the use of Cache-Control or Expires headers are very useful.  Where YSlow  and Page Speed differ is in the recommendation for how long the content should be cached for.  YSlow recommends 2 days while Page Speed suggests 30 days, I have to say I agree with YSlow on this point.  If there is no way for a browser to recognize if the content that has been cached has changed then a static 30 days expiration may be result in stale content being served to end users.  To use an expiration like 30 days the development process has to change as well to include some sort of versioning to prevent the browser for serving stale content.  Changing the development process isn't always possible which is why a shorter expiration may be needed.  One of the down-sides to YSlow is that they use a default value of 48 hours for the cache if objects are cached for less than this time points are deducted and a low score is provided.   Even though DevCentral uses an expiry between 2 days and 180 days 27 objects are flagged by YSlow as not having a far-future expires.  The items that are flagged are those having a 2 day expiry cache-control headers are set to public, s-maxage=14400, max-age=172800, I believe what is happening here is that between the item being cached and YSlow running the analysis just enough milliseconds have passed to have the content be just under 2 days and therefore trigger the warning. It would be nice if you could configure what was an appropriate expires for your business and have the tools use that value instead of having a value imposed on you. 

Compression

Using GZIP is a great optimisation technique and should be used whenever possible.  While there are about 20 text files on the DevCentral homepage there are 2 that are not compressed which is picked up and flagged by both tools.  It is unfortunately not always possible to compress every single text file.  I have spent hours with customers trying to debug why an application doesn't work when compression is enabled, in the end it turns out to be a single script file that when compressed causes the page functionality to break, disabling compression for the script in question resolves the problem.  If there are multiple compressed files on a page and only 1 or 2 that aren't compressed there may be a reason for it.

Reduce DNS Lookups

Page Speed and YSlow both recommend reducing the number of DNS lookups and have identified the domains the content is coming from.  YSlow provides a score of A even though there are 5 domains.  Page Speed suggests eliminating some of these items - unfortunately that can't be done as these are third party resources that are used for various analysis and tracking - one of which just happens to be from Google.  It seems like YSlow is a little smarter in identifying what these are for and that they can't be reduced.  This  recommendation is actually a little puzzling to me as one way to speed up page download is to spread the requests across multiple domains to allow more items to download in parallel.  Page Speed provides this as a recommendation as well but doesn't this contradict the recommendation to reduce DNS lookups.

 

Generally speaking both tools are valuable in understanding where a site may be slow and where improvements can be made but make sure to investigate whether or not the recommendations work for your application.  There may be reasons why things are the way they are.  It will be interesting to see how these continue to evolve. 

Read the original blog entry...

More Stories By Dawn Parzych

Dawn Parzych is a Technical Product Marketing Manager at Instart Logic. Dawn has had a passion for web performance for over 15 years with a focus on how to make the web faster. As a technical product marketing manager at Instart Logic, she researches and writes about trends in the web performance space and how they impact the user experience. Prior to joining Instart Logic, Dawn worked at F5 Networks, Gomez & Empirix.

@ThingsExpo Stories
SYS-CON Events announced today that Golden Gate University will exhibit at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. Since 1901, non-profit Golden Gate University (GGU) has been helping adults achieve their professional goals by providing high quality, practice-based undergraduate and graduate educational programs in law, taxation, business and related professions. Many of its courses are taug...
What is the best strategy for selecting the right offshore company for your business? In his session at 21st Cloud Expo, Alan Winters, U.S. Head of Business Development at MobiDev, will discuss the things to look for - positive and negative - in evaluating your options. He will also discuss how to maximize productivity with your offshore developers. Before you start your search, clearly understand your business needs and how that impacts software choices.
SYS-CON Events announced today that Ryobi Systems will exhibit at the Japan External Trade Organization (JETRO) Pavilion at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. Ryobi Systems Co., Ltd., as an information service company, specialized in business support for local governments and medical industry. We are challenging to achive the precision farming with AI. For more information, visit http:...
As popularity of the smart home is growing and continues to go mainstream, technological factors play a greater role. The IoT protocol houses the interoperability battery consumption, security, and configuration of a smart home device, and it can be difficult for companies to choose the right kind for their product. For both DIY and professionally installed smart homes, developers need to consider each of these elements for their product to be successful in the market and current smart homes.
SYS-CON Events announced today that Avere Systems, a leading provider of hybrid cloud enablement solutions, will exhibit at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. Avere Systems was created by file systems experts determined to reinvent storage by changing the way enterprises thought about and bought storage resources. With decades of experience behind the company’s founders, Avere got its ...
High-velocity engineering teams are applying not only continuous delivery processes, but also lessons in experimentation from established leaders like Amazon, Netflix, and Facebook. These companies have made experimentation a foundation for their release processes, allowing them to try out major feature releases and redesigns within smaller groups before making them broadly available. In his session at 21st Cloud Expo, Brian Lucas, Senior Staff Engineer at Optimizely, will discuss how by using...
In this strange new world where more and more power is drawn from business technology, companies are effectively straddling two paths on the road to innovation and transformation into digital enterprises. The first path is the heritage trail – with “legacy” technology forming the background. Here, extant technologies are transformed by core IT teams to provide more API-driven approaches. Legacy systems can restrict companies that are transitioning into digital enterprises. To truly become a lead...
SYS-CON Events announced today that Yuasa System will exhibit at the Japan External Trade Organization (JETRO) Pavilion at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. Yuasa System is introducing a multi-purpose endurance testing system for flexible displays, OLED devices, flexible substrates, flat cables, and films in smartphones, wearables, automobiles, and healthcare.
SYS-CON Events announced today that CAST Software will exhibit at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 - Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. CAST was founded more than 25 years ago to make the invisible visible. Built around the idea that even the best analytics on the market still leave blind spots for technical teams looking to deliver better software and prevent outages, CAST provides the software intelligence that matter ...
SYS-CON Events announced today that Daiya Industry will exhibit at the Japanese Pavilion at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. Ruby Development Inc. builds new services in short period of time and provides a continuous support of those services based on Ruby on Rails. For more information, please visit https://github.com/RubyDevInc.
SYS-CON Events announced today that Evatronix will exhibit at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. Evatronix SA offers comprehensive solutions in the design and implementation of electronic systems, in CAD / CAM deployment, and also is a designer and manufacturer of advanced 3D scanners for professional applications.
As businesses evolve, they need technology that is simple to help them succeed today and flexible enough to help them build for tomorrow. Chrome is fit for the workplace of the future — providing a secure, consistent user experience across a range of devices that can be used anywhere. In her session at 21st Cloud Expo, Vidya Nagarajan, a Senior Product Manager at Google, will take a look at various options as to how ChromeOS can be leveraged to interact with people on the devices, and formats th...
SYS-CON Events announced today that Taica will exhibit at the Japan External Trade Organization (JETRO) Pavilion at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. Taica manufacturers Alpha-GEL brand silicone components and materials, which maintain outstanding performance over a wide temperature range -40C to +200C. For more information, visit http://www.taica.co.jp/english/.
SYS-CON Events announced today that SourceForge has been named “Media Sponsor” of SYS-CON's 21st International Cloud Expo, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. SourceForge is the largest, most trusted destination for Open Source Software development, collaboration, discovery and download on the web serving over 32 million viewers, 150 million downloads and over 460,000 active development projects each and every month.
Enterprises have taken advantage of IoT to achieve important revenue and cost advantages. What is less apparent is how incumbent enterprises operating at scale have, following success with IoT, built analytic, operations management and software development capabilities – ranging from autonomous vehicles to manageable robotics installations. They have embraced these capabilities as if they were Silicon Valley startups. As a result, many firms employ new business models that place enormous impor...
SYS-CON Events announced today that TidalScale will exhibit at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. TidalScale is the leading provider of Software-Defined Servers that bring flexibility to modern data centers by right-sizing servers on the fly to fit any data set or workload. TidalScale’s award-winning inverse hypervisor technology combines multiple commodity servers (including their ass...
SYS-CON Events announced today that MIRAI Inc. will exhibit at the Japan External Trade Organization (JETRO) Pavilion at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. MIRAI Inc. are IT consultants from the public sector whose mission is to solve social issues by technology and innovation and to create a meaningful future for people.
In his Opening Keynote at 21st Cloud Expo, John Considine, General Manager of IBM Cloud Infrastructure, will lead you through the exciting evolution of the cloud. He'll look at this major disruption from the perspective of technology, business models, and what this means for enterprises of all sizes. John Considine is General Manager of Cloud Infrastructure Services at IBM. In that role he is responsible for leading IBM’s public cloud infrastructure including strategy, development, and offering ...
As hybrid cloud becomes the de-facto standard mode of operation for most enterprises, new challenges arise on how to efficiently and economically share data across environments. In his session at 21st Cloud Expo, Dr. Allon Cohen, VP of Product at Elastifile, will explore new techniques and best practices that help enterprise IT benefit from the advantages of hybrid cloud environments by enabling data availability for both legacy enterprise and cloud-native mission critical applications. By rev...
SYS-CON Events announced today that NetApp has been named “Bronze Sponsor” of SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. NetApp is the data authority for hybrid cloud. NetApp provides a full range of hybrid cloud data services that simplify management of applications and data across cloud and on-premises environments to accelerate digital transformation. Together with their partners, NetApp emp...