When cache is automatically refreshed?

Following rules are used:

• Category saves triggers to clear all cache because of top navigation, that appears across all site pages
• Product changes triggers invalidation of product, quickshopping and related category pages
• Cms page changes will update cms page url only. Home page will be updated too, if changed page is set as homepage
• Product review triggers review, review listing, related product and category pages refreshing.
• Product Tag changes makes the product and related tag list pages to refresh
• CatalogRules update triggers invalidating of related product and category pages
• New Order invalidates purchased product pages

Automatic cache updating can be disabled at System > Configuration > TM > Cache > General options. In this case you will be notified about cache invalidating, when one of the supported events occurs.