
We Started Putting Unpopular Assets in Memory - jgrahamc
https://blog.cloudflare.com/why-we-started-putting-unpopular-assets-in-memory/
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uluyol
Summary: They used to cache things immediately onto SSDs. This causes lots of
wear because you end up writing lots of data that it turns out you didn't want
to. To fix this, they first stage things in memory. If an item is popular
enough and worth caching, they store it onto disk (hence reducing the number
of writes on the SSD). Both with the old and new approaches, they rely on the
OS page cache to keep hot items in memory.

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chmaynard
Great article! The author (Yuchen Wu) is a master communicator.

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manigandham
I don't think this is an uncommon strategy. It's used in other caching
scenarios where data is put into the fastest tier, then expire or age out to
slower tiers as necessary.

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matsur
Typical tiered memory hierarchies put _more_ popular assets in faster tiers of
memory. This post describes the opposite: putting _less_ popular assets in
faster tiers of memory to improve performance of the system.

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manigandham
I'm talking about the initial location (which is what this article covers).

Of course the most popular content _stays_ in faster tiers, but the difference
is _placing it there first_ and aging it out instead of _promoting it after_
from slower tiers.

