# connect() - why are you so slow?

<https://blog.cloudflare.com/linux-transport-protocol-port-selection-performance>

- Host: [blog.cloudflare.com](https://links.thingelstad.xyz/hosts/blog.cloudflare.com/)
- Saved: February 12, 2024 (2024-02-13T04:03:42Z)
- Record: https://links.thingelstad.xyz/links/0d6093acfd3e/
- JSON: https://links.thingelstad.xyz/links/0d6093acfd3e.json

## What Jamie wrote

Cloudflare has some great investigations into super edge case performance stuff that only matters at their scale. This was a fun sleuth!

> At this point, we can summarize that the odd/even port split is what is causing our performance bottleneck. And during the investigation, it was not obvious to me (or even maybe you) why the offset was initially calculated the way it was, and why the odd/even port split was introduced. After some git-archaeology the decisions become more clear.

The odd/even thing here would never have been suspected without the detailed analysis.

## Facts

- Kind: [Page](https://links.thingelstad.xyz/kinds/page/)

## Appears in

- [WT277: Weekly Thing 277 / Privacy, Scammed, OmniFocus](https://weekly.thingelstad.com/archive/277/), Notable

## Same host

- [Thanksgiving 2023 security incident](https://links.thingelstad.xyz/links/49e21a8dca7d/) (blog.cloudflare.com, February 5, 2024)
- [A look at Internet traffic trends during Super Bowl LVIII](https://links.thingelstad.xyz/links/18e525b8c4ca/) (blog.cloudflare.com, February 12, 2024)
- [Undersea cable failures cause Internet disruptions for multiple African countries](https://links.thingelstad.xyz/links/d066f7f7441b/) (blog.cloudflare.com, March 14, 2024)
- [Cloudflare’s public IPFS gateways and supporting Interplanetary Shipyard](https://links.thingelstad.xyz/links/f2b520f8ff76/) (blog.cloudflare.com, May 16, 2024)
- [Patent troll Sable pays up, dedicates all its patents to the public!](https://links.thingelstad.xyz/links/0d92a6bff251/) (blog.cloudflare.com, October 5, 2024)

## Saved the same week

- [“Wherever you get your podcasts” is a radical statement - Anil Dash](https://links.thingelstad.xyz/links/147217b45286/) (anildash.com, February 12, 2024)
- [They gave local news away for free. Virtually nobody wanted it. - Columbia Journalism Review](https://links.thingelstad.xyz/links/b5a6c3d711a0/) (cjr.org, February 12, 2024)
- [METAstasis | No Mercy / No Malice](https://links.thingelstad.xyz/links/9bcf322efdaf/) (profgalloway.com, February 12, 2024)
- [How I got scammed (05 Feb 2024) – Pluralistic: Daily links from Cory Doctorow](https://links.thingelstad.xyz/links/c39fbb54075d/) (pluralistic.net, February 12, 2024)
- [Ask security questions](https://links.thingelstad.xyz/links/e739b5da6ab8/) (vitalik.eth.limo, February 12, 2024)

## Elsewhere

- Wayback Machine: https://web.archive.org/web/*/https://blog.cloudflare.com/linux-transport-protocol-port-selection-performance