Summary

Table 6.1 shows the effects of various optimization and compression levels on the sample home page. By removing unnecessary whitespace, and meta and closing tags, SpaceAgent reduced the page by 27 percent, to 100,562 bytes. Manually optimizing the page to optimize the CSS and JavaScript, and doing some table trimming would reduce this figure well below 100K.

Manual optimization using the preceding techniques brings down the page to a little under 48K. With a 56K modem humming along at 4.5K/second on a clean line, the HTML portion of the HTML page would now load in a little over 10 seconds. Utilizing compression would bring down the optimized page to 8.4K, which would load in just over two seconds. Sub-eight second display times are desirable, and a two-second load is nearly ideal. The compressed version of the optimized page is over 16 times smaller than the original.

Keep in mind that this is a partial optimization. Fully optimizing the page by reworking the tables, using abbreviated links, using optimized CSS and positioning, and simplifying or eliminating the JavaScript would mean even more savings. Compression would achieve similar ratios of 80 to 85 percent over the optimized HTML. HTML optimization and compression can make a big difference in the perceived and actual display speed of your pages and will keep your site visitors coming back for more.