This document discusses techniques for improving web performance. It begins with research on how caching and cookies impact performance. It then outlines 14 rules for optimizing performance, such as making fewer HTTP requests, using content delivery networks, gzipping components, placing scripts at the bottom of pages, and avoiding redirects. Case studies demonstrate how following these rules can significantly improve page load times. The document emphasizes starting performance improvements by focusing on front-end optimizations and advocates evangelizing best practices.
17. Impact of Cookies on Response Time 80 ms delay dialup users +78 ms 156 ms 3000 bytes +63 ms 141 ms 2500 bytes +47 ms 125 ms 2000 bytes +31 ms 109 ms 1500 bytes +16 ms 94 ms 1000 bytes +1 ms 79 ms 500 bytes 0 ms 78 ms 0 bytes Delta Time Cookie Size keep sizes low
44. Rule 10: Minify JavaScript minify inline scripts, too no yes no no yes yes yes no no no Minify External? no www.youtube.com yes www.yahoo.com no www.wikipedia.org no www.myspace.com yes www.msn.com yes froogle.google.com no www.ebay.com no www.cnn.com no www.aol.com no www.amazon.com Minify Inline?
57. Case Study: Mail Mail Classic User Workflow mail.yahoo.com view inbox folder read messages (x3) compose message confirm send total time: Time 2.40 s 4.98 s 6.39 s 2.21 s 2.10 s 18.08 s Time 12.48 s 1.52 s 1.53 s 0.34 s 0s 15.87 s Delta +420% -70% -76% -85% -100% -12%
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60. Ten Top U.S Web Sites 139K 178K 106K 205K 221K 18K 275K 502K 182K 405K Page Weight 9.6 sec 5.9 sec 6.2 sec 7.8 sec 9.3 sec 1.7 sec 9.6 sec 22.4 sec 11.5 sec 15.9 sec Response Time D www.youtube.com A www.yahoo.com C www.wikipedia.org D www.myspace.com F www.msn.com A froogle.google.com C www.ebay.com F www.cnn.com F www.aol.com D www.amazon.com YSlow Grade