PageSpeed Module - Optimizing For Bandwidth

PageSpeed's default RewriteLevel of CoreFilters is designed to reduce latency, incurring a small risk of page breakage. A related goal, bandwidth reduction, can be achieved with close to zero risk of web-site breakage:

Apache:

ModPagespeedRewriteLevel OptimizeForBandwidth

Nginx:

pagespeed RewriteLevel OptimizeForBandwidth;

This option is suitable for use in a root configuration at a hosting service, CDN, or multi-site setup, in conjunction with InheritVhostConfig. In this mode, PageSpeed does not alter HTML at all. It compresses and transcodes images in place, and minifies JavaScript and CSS. By avoiding changes to URL syntax and to HTML, the potential problem of user-written JavaScript encountering unexpected DOM elements is elimimated. There is still latency benefit due to the reduced size of resources, as well as substantial bandwidth reduction.