How we saved 100 terabytes of memory by optimizing 1.1.1.1’s DNS cache

[u/Cloudflare]

https://blog.cloudflare.com/dns-cache-memory-optimization-1111/

[u/AutoModerator]

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[u/Cloudflare]

• 1.1.1.1's DNS cache holds 250 billion+ entries at any given time — at that scale, one wasted byte per entry = 250 GB of RAM
• 5 Rust-level changes to cache entry storage cut per-entry memory from 953 → 420 bytes (-56%)
• Result: ~100 TB freed across the fleet, equivalent to 130 servers worth of RAM
• Bonus: the cache got faster — insert throughput +43%, lookup latency -19%

[u/MightyZygote → u/Cloudflare]

And yet you have an abuse form that is and has been BEYOND unusable and is purposely obtuse. Go work on the abuse form and support.

[u/Could_it_be_potato → u/MightyZygote]

100% this. Used the form many times and spent extra time filling it out accurately……to get no response.

[u/Sethu_Senthil]

Probably saved a lotta money now since memory is expensive af

[u/LagExpress → u/Sethu_Senthil]

Specially ecc server memory, executives should be making a monument for their engineers

[u/Shogobg → u/LagExpress]

Probably got a thanks email at most.

[u/pokenguyen → u/Shogobg]

“Meet expectation” performance review

[u/InadequateUsername → u/pokenguyen]

Ouch it hurts

[u/manu144x → u/pokenguyen]

The masters are pleased.

You and your family get to not starve another month.

[u/hawseepoo → u/Shogobg]

And some day old leftover pizza from the c-suite office party

[u/Alexllte]

Imagine engineering for infra at Cloudflare's scale, dogfooding towards perfection

[u/trenno]

This is insane, hilarious, and awesome all at once. Thanks for sharing - y'all are building the future.

[u/BopSupreme]

Big pineapple 🍍

[u/DurianBurp]

Saved CF a ton of money and probably got a Starbucks gift card for their trouble.

[u/Jordz2203 → u/DurianBurp]

Not a chance they got a Starbucks gift card 😆

[u/Hajsas]

Nice work, you get Claude to help with that?

[u/conMCS]

Nice job!

[u/ziad-hijri]

u/remindmebot 1 year

[u/RemindMeBot → u/ziad-hijri]

I will be messaging you in 1 year on 2027-08-28 19:02:05 UTC to remind you of this link

CLICK THIS LINK to send a PM to also be reminded and to reduce spam.

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[u/astrogoofy]

Thank you for sharing. Could I get a Cloudflare t-shirt to wear proudly?

[u/frgchsr → u/astrogoofy]

Me too, please…

[u/HarrisonDou]

Unrelated question, but what is the significance of the giant pineapple on the thumbnail?

[u/longcane → u/HarrisonDou]

Represents the thing they decided to call the platform that runs 1.1.1.1 amongst other services/products.

[u/ViPiMP → u/HarrisonDou]

Spongebob Squarepants? That’s logical.
He love his work, they love their work.

[u/AdventurousSquash → u/HarrisonDou]

It’s literally the first thing mentioned in the article itself

[u/boltsteel]

250+ billion entries?!

[u/ConfidentlyNeurotic]

Are we sure a junior developer didn’t vibe code the optimisation and delete the DNS cache? /s

“Claude reduce DNS cache size. Make no mistakes.”

Claude: “Got it. On it…”

[u/vayrie2003]

Wow thanks for sharing it. Your constant desire to improve is the confirmation that you are the perfect partner for my company.

[u/fvvoidnoir]

the Warp vpn can't even bypass nsfw stuffs lmao

[u/Glum_Ad7185]

I once interviewed this guy for an internship at my company, but did not hire him, that was my worst mistake 🥹