/dk/tohojo/blog

TCP zero-copy is a feature of the Linux kernel that makes it possible to send and receive data without incurring an extra copy between kernel memory and the memory buffer that holds the final data (in userspace, or even in the memory of a different device…

It used to be the case that eBPF programs were very limited in what they could do in the kernel; no loops, only a very limited number of instructions, etc.

I guess it was inevitable that I would have to write something about AI here, although I’ve been putting it off for a while now.

As I embark on yet another cross-continent train journey, I find myself reflecting on the experience of travelling slowly.

I was devastated to learn that Dave Täht passed away.

This is a writeup of an issue I discovered back in 2019 with my internet provider at the time.

This is an open letter in which the open source community urges the European Commission to keep funding the NGI initiative from 2025 and on.

I was recently made aware of an interesting issue, which appears to be a pretty fundamental property of the departure time-based traffic shaping that is used by many BPF-based data planes, such as in the Cilium Bandwidth Manager.

An interesting feature that I implemented about a year ago (it first appeared in the 5.18 kernel), is the ability to make the BPF_PROG_RUN syscall run in a “live packet mode” for XDP.

To kick things off in this second era of my blog (ha!)

So it seems more than four years have passed since I wrote that last “nearing the end” entry.

After almost five years of work, I am finally ready to defend my PhD thesis this Friday, November 23rd at 09:15 CET.

The university lab I keep my testbeds in had to be reorganised a few months ago, and everything moved into a smallish server room (where before it was in a larger office space).

I tend to eschew the normal practice of bridging WiFi and Ethernet networks in my private setups, instead running them on separate subnets and routing between them.