March 19, 2015
Bookmarklets & ImageMagick @ Toronto Web Performance Meetup
A Performance Bookmarklet by @micmro
Check these out:
- DOM Monster does DOM analysis
- Perfmap visually annotates your page with performance info
- Waterfall shows a waterfall similar to Chrome’s dev tools
- Mike is working on this bookmarklet which does lots of stuff
other neat bits
- there are browser APIs for getting timing info about page loads
- there is a http header for getting timing info in cross-domain requests
- opening Chrome Dev tools can impact performance testing – for example slower load times due to downloading source maps
- image caching images probably impacts results that these bookmarklets report, so be aware of whether caching is happening or not when looking at results
How to use ImageMagick by @newtron
- using responsive images well means generating lots of different sized images source art
- ImageMagick is a command line tool available on many web servers that can help with resizing images, but it is horrible at optimizing images out of the box
- Dave spent a ton of time testing out different compression & optimization settings to find the best balance
- Dave integrated his findings into grunt-respimg, a Grunt task you can integrate in your build system