Convoluted. That’s how we’d describe traditional cache management. You need to determine how long every single object will remain cached before its purged from the cache. It’s called Time-to-Live (TTL). But of course it’s not that simple. You actually have to weigh the potential costs and benefits of storing each and every object for more time or less. Set your TTL too long and your customers dine on stale data that’s no longer relevant. Set it too short and your origin server will get hit too often, which of course diminishes the advantage of using a CDN in the first place.
Most CDNs allow only a limited number of manual purges. And when you do purge, they’ll tell you to allow anywhere from X hours to Y days. We don’t have that kind of patience. And we assume you don’t either.
Fastly offers a better way.
Instant Purge. Check this out.
You can set the TTL to an arbitrarily long time. Regardless, when you or your database app updates an object, the old object is automatically purged in less than two seconds from every server in our network. You can even specify a set of objects by surrogate key to purge simultaneously, or purge the entirety of your cached data. With a single command. Done and done.
Instant Purge. It’s what allows us to cache millions upon millions of dynamically generated objects without serving up stale data. It’s what allows you to cache all your content intelligently. We think you’ll even dramatically boost your cache-hit ratio.
Getting rid of old stuff feels so good. Especially when it’s instant.