Infrastructure @SlackHQ. Distributed systems engineer. I have of late - but wherefore I know not - lost all my data.
Joined March 2007
- Tweets 6,182
- Following 468
- Followers 6,600
- Likes 1,798
334 Photos and videos
Pinned Tweet
16 Dec 2022
Ok, that’s enough. I’ll try @henry_r@hachyderm.io.
Many good and ethical reasons to leave, but it’s the daily performance of utter mediocrity by Musk that does it for me.
He’s not funny, he’s not kind, he’s not clever, he’s not creative. I don’t owe him any of my attention.✌️
3
2
23
10,013
8 Nov 2024
Scriptwriters note: As metaphors for the last week go, this spontaneously exploding car on our street at midnight was a little too on-the-nose.
5
718
1 Nov 2024
Extremely confused by the woman at the Cure show with a Robert Smith tattoo on one arm and a Nigel Farage portrait on the other.
4
589
22 Oct 2024
I’m no expert, but I think the final sentence could use an Oxford comma.
4
593
1 Oct 2024
A friend is looking for speakers on AI on healthcare for a medical conference in London. Any recommendations?
1
585
2 Aug 2024
hello I am a principal engineer who pays AWS $120 a year because I cannot figure out how to delete everything from Glacier.
1
19
2,142
25 Jul 2024
I’ve been saying this for ten years!
(From slideshare.net/slideshow/pwl…)
25 Jul 2024
Let's assign CAP to the cabinet of curiosities: brooker.co.za/blog/2024/07/2…
If you’re an experienced distributed systems person teaching new folks about trade-offs in your space, please don’t start with CAP. Tons of more interesting, more instructive, trade-offs.
1
18
4,034
25 May 2024
Don’t want to give the punchline away, but as a veteran Nethack player, I knew what it was after the first couple of tweets.
24 May 2024
So here's a story of, by far, the weirdest bug I've encountered in my CS career.
Along with @maciejwolczyk we've been training a neural network that learns how to play NetHack, an old roguelike game, that looks like in the screenshot. Recenlty, something unexpected happened.
6
1,522
10 Apr 2024
I just fixed a DB overload problem at Slack (in dev) by manually typing 100 one-word messages into a channel, in case you were wondering what “senior” engineers do all day.
9
5
87
10,965
9 Jan 2024
Fault models are like threat models and reliability is only meaningful with respect to a fault model.
Can’t read a dist sys paper without someone defining a system, or fault, model.
The P in CAP is actually a fault model.
9 Jan 2024
You ever see the same term pop up in a few places and think "hmmm"?
@TigerBeetleDB often talks of "fault models". Wonder if theres more to this idea than I think.
(Paper is "A Transaction Model", Jim Gray, IBM Research Laboratory 1980)
2
11
3,075
21 Dec 2023
Tell me jepsen.io/analyses/mysql-8.0… is written by Peter and Kyle without etc etc.
6
1,194
19 Nov 2023
In my defence $henry_sucks_and_this_outage_is_his_fault did seem a bit pointed.
19 Nov 2023
I’ve had a PR that fixed a *production outage* blocked once because one of the engineers did not appreciate the variable name I’ve chosen
10
2,940
19 Nov 2023
if all goes well I’ll get through this whole fiasco without finding out what “e/acc” means.
1
6
2,453
19 Nov 2023
I wrote up Adaptive Radix Tries a few years ago, including details of how the the adaptations facilitate CPU-efficient search implementations:
the-paper-trail.org/post/art…
18 Nov 2023
Reading the Adaptive Radix Tree paper - Having the realisation that trie is such an underrated data structure. Wondering why we should use any other data structure for in memory database indexes.
Here are some rough notes from the paper ..
Tree based indexes (e.g. binary search tree or b-tree needs special care for cache friendliness, are expensive for updates and can show pipeline stall for branch misprediction.
Hash based indexes are great for point queries, not so for range queries, are expensive to grow with O(n) complexity for reorganisation.
Tries have O(k) complexity where k is the size of the key, which means independence from n (that is a HUGE plus). The trie height can be controlled through the span s of the radix tree and is usually smaller than the height of a binary search tree. Hence search can be faster - O(k) compared to O(k lg n) in BSTs. One problem with tries is they can have higher space consumption compared to trees. But ART manages this through variable sized data structures for inner nodes and leaves.
The paper is a great read ..
3
22
166
39,599
29 Dec 2022
A friend is in desperate need of a small plane to transfer her and her critically ill 4 year old son to Phoenix from New York in the coming few days. They have the pilot, money for fuel, fees and medical staff, but are in urgent need of the plane itself.
Can you help?
4
21
13
20,513
29 Dec 2022
If you know someone who might be able to help, or you got a plane under the tree this year, please reach out to me directly so that I can put you in touch 🙇
1
1
3,066
15 Dec 2022
hey kids - you can forge an excellent career in software engineering by doing the exact opposite of almost everything Uncle B*b tells you.
2
5
54
7 Dec 2022
This is so terribly sad. The moment I started tweeting about compilers, Chris reached out to me and offered his time to sit and dissect TruffleRuby. I never was able to take him up on it, but meant to reach out now that I was in his timezone. What an awful, awful loss.
7 Dec 2022
I'm heartbroken to share this news about our dear friend and colleague, @ChrisGSeaton.
ALT Screenshot of a message from Shopify's Ruby and Rails Infrastructure team that includes: Our dear friend and colleague Chris Seaton passed away last Saturday, December 3rd. Chris was an important part of our team at Shopify, and a notable figure in the Ruby community, and we are deeply saddened by our collective loss. Chris accomplished much in his life. He completed a Ph.D., rose to be Squadron Leader in the British Army Reserve, and started a young family. Chris began the TruffleRuby project in 2013 as an intern at Oracle Labs and stewarded it into a full-fledged Ruby implementation. Chris advanced the state of the art in dynamic language optimization, co-authoring 16 publications, contributing to countless others, and establishing both the Ruby Bibliography archive of Ruby research publications and the Ruby Compiler Survey. For his efforts, he was a Ruby Prize finalist in 2016. Chris’s papers, essays, and code contributions are currently archived at chrisseaton.com.
8
2 Dec 2022
Is it actually a good thing that there are lawyers volunteering to be the main characters of this Twitter suit?
1