Magento Code Swarm
Visualization using code swarm of all changes made to the Magento code base up to 1.3.2. Check out some other visualizations by clicking on the “code swarm” tag.
Music by Feist.
How to create QR codes using Google Charts
I was tinkering with auto generating QR codes a while ago when I discovered (to my surprise) that the Google Charts API actually had a pretty slick option to generate this on demand.
All you have to do is to pass the url or text that you wish to be encoded to the Charts API. For example, the link to create the image above is:
http://chart.apis.google.com/chart?cht=qr&chs=500x500&chld=H&chl=http://tumblelog.jauderho.com/
I would be interested in learning more where others are using QR codes (or similar codes such as Microsoft Tag)
References:
Improving Magento Performance
It appears that there are quite a few complaints on the forums about Magento being slow and this is probably true with an out of the box installation. There are quite a few things that can be done to improve things and response time in general.
The following shows the before and after times as recorded by Pingdom for http://furoshiki.com/. The initial installation reflected a stock LAMP based installation with average response time of about 9 seconds.
With a switch to nginx as well as tuning of various components, the response time subsequently dropped by over half to about 4 seconds which is in the sweet spot for ecommerce sites.
The following are some of the changes made:
- Switch to using nginx as a front end.
- Set Expires to far in the future
- Utilize PHP FPM.
- Implement APC
- PHP tuning
- MySQL tuning
Before (8.9 seconds):
After (3.9 seconds):
As you can see, the site is now very responsive (buy some furoshiki while you are there). I am investigating additional improvements as traffic increases.
Why does this matter? Surveys have shown that there is a correlation from site response time to sales with higher abandonment rates with a slow site. For further reading, see:
- Are Your Website Response Times Costing You Sales?
- Website Response Time - 4 Seconds
- Site Response Time
How is your site doing? Test it now using Pingdom.
Magento Javascript Loading Bug
While looking at Magento performance via Pingdom, I noticed that Pingdom was indicating that a particular URL was not being loaded. Upon closer inspection, it turned out to be the Javascript loading php script. Obviously, this is not a good sign so I decided to investigate further.
It turns out that the URL used includes an & that is not properly understood by some HTTP clients including pingdom and curl. To fix this, you need to edit app/code/core/Mage/Page/Block/Html/Head.php and change the 2 instances of “&,” to “&”.
I have also published the change at github so you may use that if you wish.
On a different note, it is probably not the best idea to aggregate Javascript in such a fashion. As noted in Cal Henderson’s Serving Javascript Fast,
According the letter of the HTTP caching specification, user agents should never cache URLs with query strings. While Internet Explorer and Firefox ignore this, Opera and Safari don’t - to make sure all user agents can cache your resources, we need to keep query strings out of their URLs.
While Magento is notable for its flexibility,in general it’s a good idea to aggregate all the JS files and send it down the pipe just once with a long Expires setting rather than having different pages with various combinations of Javascript files concatenated together as a) you lose the benefit of caching the js and b) you are potentially resending portions of the same data multiple times.
