Categories
General

Interesting Paper

COZ: Finding Code that Counts with Causal Profiling

This paper is worth reading just for one neat idea. Everyone wants to make their code fast. If you had a magic wand that enabled you to ‘make function X’ faster then you could measure the impact on the performance of the system and you would know how important said function is to the overall performance. Obviously, this is a bit silly because if you had such a wand, you would just use it everywhere and not have to optimize the code yourself.

This paper inverts this idea. Instead of making function X faster, they leverage a neat trick to make every other function slower. Then the relative importance of the function to overall system performance can be measured. The results are impressive. Neat!

Note: The paper doesn’t just look at whole functions.

Categories
General

The world in which IPv6 was a good design

https://apenwarr.ca/log/20170810

Categories
General

A bit of me died when I turned off my email server

As of a couple days ago, for the first time since 1997, I no longer run a production email server – I’m a bit sad about it.

I’ve long been a proponent of distributed communications systems like email. I spent a lot of time with XMPP but eventually had to concede I was never going to get my non-uber-geek contacts to use it. However, I stubbornly continued hosting my personal email on my own server. It wasn’t a huge amount of work as I had experience running email servers with thousands of users so I didn’t have to learn anything new.

Over time keeping up on the spam and email authentication tools has gotten to be more work and I’ve had some problems with Outlook classifying my domain’s email as spam. Since neither the server’s addresses nor the domain have been in any email blacklists, I presume that some of the delivery problems are simply that my little one inbox email server doesn’t generate enough traffic to build a good reputation. Add to this that my trusty server, which has been running without failure since 2007, is long overdue for a component failure made it time to move on.

Categories
General

AF_XDP and io_uring

io_uring is a new interface for asynchronous I/O to the Linux kernel. The LWN article and the io_uring design doc are both worth reading. I’ve been playing with AF_XDP a bit and after reading the io_uring doc it seemed like some of the io_uring ideas would be great enhancements to AF_XDP. Happily, one of the more interesting features, adding a wake-up flag to AF_XDP to avoid syscalls, was recently posted to Netdev.

Categories
General

Shaping via Timer Wheels

https://platformlab.stanford.edu/Seminar%20Talks/2018/David_Wetherall.pdf

https://www.cc.gatech.edu/~amsmti3/files/carousel-sigcomm17.pdf

Related talk: https://www.youtube.com/watch?v=MAni0_lN7zE

Categories
General

https://ferd.ca/queues-don-t-fix-overload.html

Categories
General

Conservative Memory Lane Is A Nightmare On Elm Street

https://politicalpotshots.wordpress.com/2019/01/30/conservative-memory-lane-is-a-nightmare-on-elm-street/amp/?__twitter_impression=true

Categories
General

99 Good News Stories You Probably Didn’t Hear About in 2018

https://medium.com/future-crunch/99-good-news-stories-you-probably-didnt-hear-about-in-2018-cc3c65f8ebd0

Categories
General

Amazon meeting culture

https://www.businessinsider.com/bezos-admits-amazon-has-the-weirdest-meeting-culture-2018-4

Categories
General

World War 1

Tomorrow is Remembrance Day. This reminded me of something I’ve been meaning to post for some time.

A year or so ago I stumbled on Dan Carlan’s Hardcore History podcast. The first series I listened to is called Blueprint for Armageddon which is about World War 1. Listening to this podcast series completely changed my view of WW1. We see and hear so much more about WW2 due to the strong good vs. evil narrative and the existence of much better pictures and video that it’s easy to forget how truly brutal and transformative WW1 was.

One small example, WW1 was the first time that the great powers fought a war with machine guns. This resulted in crazy stuff like Napolean era tactics and uniforms being used on machine gun nests during the early years of the war resulting in incredible casualties.

I can’t recommended listening to this podcast series enough. I almost don’t want to mention this because I don’t want to scare you off… the series is five episodes long and each episode is two to three hours. I listened to it in chunks over about six months.