

Things Caches Do (2008) - dedalus
http://tomayko.com/writings/things-caches-do

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makmanalp
This is neat. There is one more case, where the cache is kept valid because
the condition that makes it invalid is known. So, for example, if I have a
message list page cached, I can simply invalidate the cache for that page when
I add a new message for that specific user. Depending on the use case, I might
want to even immediately repopulate that cache with the new info.

This is really the ideal scenario since things are always cached and requests
don't even need to hit the dynamic site, but obviously this can't always
happen since sometimes you just don't know.

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pjbringer
Also, cache invalidation can actually be cache replacement. Otherwise, under
very high load, you risk cache stampede.

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projectileboy
I know it's an oldie, but thanks for posting this; I hadn't seen it before.
Ryan Tomayko writes some quality stuff; I remember around the time Git was
becoming popular, I sort of didn't understand the hype right away, and Ryan
posted a great explanation ([http://tomayko.com/writings/the-thing-about-
git](http://tomayko.com/writings/the-thing-about-git)) that turned a light
bulb on in my head.

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dc2447
This article is showing it's age. How likely is it like we are going to cache
the 'welcome page' for Bob or Alice in 2013? It's pretty unlikely unless there
is either zero personalisation on the welcome page or there is some Javascript
hacked in to personalise the page.

More interesting is caching between our front ends and the back ends. Your
backends are all serving up content over http these days so caching here makes
much more sense.

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zeckalpha
That was just the example used.

