Wp-Widget-Cache – Does what the name says it does. It will cache your widgets. Super cache and hyper cache, waste a lot of time caching widgets for every single static page they create. This mod will cache the entire widget area of your website while reducing SQL queries and give you total control over the cache time of your widgets. The author of the mod does a good job of explaining the need for this mod.
If some of your page is very popular, and people keep visiting this page, then the page cache will be very helpful. But what if the user click some link and visit another page of your blog, or Google is crawling your site? Cache another whole page? Actually that’s not necessary for most time. As we all know, WordPress share the same widgets, they’re all the same, maybe on all the pages of your site. For example, the Categories widget, this maybe never change, the Archives widget, maybe changes once a month. So it’s really really not that necessary to query the database again? especially when you use a lot of widgets.
WP Widget Cache is not to replace the WP-Cache or WP Super Cache, it’s a plus for them, as it reducing the cost for caching a new page. you can set the cache time for each widget individually, seconds to years, whatever you like. For Categories widget, days maybe fine, for Recent Comments widget, seconds maybe fine.
How effective is it?
That depends on how many and what widgets you use, for www.mashget.com, the queries for home page reduce from from 69 to 19, that’s means 70% improvement.