mjb

15 ms·

151.
by mjb 3y ago
Of course RAID 5 and 6 are erasure coding. They use a code (e.g. XOR/parity) to tolerate the behavior of a binary erasure channel (BEC). Systematic codes (where some of the code stripes are just identity chunks of the data), like RAID
152.
by mjb 3y ago
One angle on this I'm particularly excited about is the formal methods/automated reasoning work the team did on Cedar: https://www.amazon.science/blog/how-we-built-cedar-with-auto... "We want to assure d
153.
Snapchange: An Open Source KVM-Backed Snapshot Fuzzing Framework(aws.amazon.com)
2 points by mjb 3y ago|0 comments
154.
by mjb 3y ago
Yeah! As far as I can tell from the research, what's going on there is primarily getting range information from the amplitude of the return (rather than delay or phase like "real" sonar uses). But still, it's very useful
155.
by mjb 3y ago
> But bat sonar, though clearly a form of perception,is not similar in its operation to any sense that we possess, and there is no reason to suppose that it is subjectively like anything we can experience or imagine. Philosophy aside, ba
156.
by mjb 3y ago
Great quote, thank you. I enjoyed Three Men in a Boat, but never read this one. It may be time to revisit Jerome.
157.
by mjb 4y ago
> We build and support Scratch to provide creative tools for anyone to explore computation in a from that is relatable and has a low floor for understanding/entry. I love this philosophy. Computing is so much more than application d
158.
by mjb 4y ago
> For example, the reliance on external infrastructure could lead to vendor lock-in, making it difficult to switch providers or move back to an in-house solution if needed. Lambda's runtime API is quite simple, and well documented (
159.
by mjb 4y ago
Explaining isolation levels is tough, and this text does a solid job. Didn't really get the comic, though. Seems to me the second person should be happy they don't get promised a snowman that then doesn't actually appear! If
160.
by mjb 4y ago
Time slicing significantly predates computers, and was quite well developed even when Erlang was analyzing it a century ago. What's surprising here isn't that time slicing works, it's that the same mechanism drives both the e
161.
by mjb 4y ago
I can definitely understand the attraction of a luxury version of regular nail clippers. But my problem with nail clippers isn't generally the quality, it's just the overall design. In my mind, "flush cutters" made for e
162.
by mjb 4y ago
I've been maintaining my blog ( https://brooker.co.za/blog/ ) for just over a decade, and I continue to do it for a couple of reasons. - I often blog about research, which has started several very interesting conver
163.
Building and Operating a Pretty Big Storage System (My Adventures in Amazon S3)(youtube.com)
4 points by mjb 4y ago|0 comments
164.
by mjb 4y ago
I find it frustrating that this article doesn't explore the tension between the "never rewrite" and ARM anecdotes. Iterating is good, but iterating to a whole new place is often impossible, and the biggest disruptions come fr
165.
The Insane Precision of the National Institute of Standards and Technology(youtube.com)
3 points by mjb 4y ago|0 comments
166.
by mjb 4y ago
Great overview! > It is highly recommended to read the source code of this amazing project and explore it yourselves - https://github1s.com/firecracker-microvm/firecracker . Yes! The Firecracker source is super reada
167.
by mjb 4y ago
If your lights are dimming, you've wrecked your THD+N by feeding your amp AC for the period the power supply filtering caps are empty. (It's even worse than AC, transiently, because of the effect of trying to refill the caps while
168.
by mjb 4y ago
I've got an SC4, and the casting and basics are very solid (for the weight and price). The compound slide is junk, but the rest is remarkably good. The DC variable speed variants are the way to go. Obviously 'big iron' is bet
169.
by mjb 4y ago
Used copies can go for incredible prices, but the book is still available new from Moore Tool: https://mooretool.com/publications.html Highly recommended.
170.
by mjb 4y ago
It's interesting that Hillel, a huge formal methods and specification advocate, sees this as a proofreading problem and not a specification one. I can't say I agree.
171.
by mjb 4y ago
> This all is just to say: it's more helpful to proliferate existing layers above the file system, than to try to change or extend the semantics of the existing FS layer. Leave it alone and put it in the "low-level tools"
172.
by mjb 4y ago
> Remember that paths are raw pointers, even in Rust. Most file operations are inherently unsafe and can lead to data races (in a broad sense) if you do not correctly synchronize file access. This is a reality that our operating systems
173.
by mjb 4y ago
The universal scalability law has this term κp(p-1), which suggests that interactions are O(p^2) for systems of p components, and those interactions happen at some relative frequency κ. Right? So why might we expect coherency to cost O(p^2)
174.
by mjb 4y ago
This is the second in a series I've slowly been working on about the "laws of physics" of database scalability. The first is here: https://brooker.co.za/blog/2023/01/30/nosql.html Obviousl
175.
by mjb 4y ago
Interesting. I've been out of this field for 20 years, and the hundredths of a degree came from my fuzzy memory. Happy to defer to your more recent knowledge.
176.
by mjb 4y ago
> PS. Do not ever approach a radar, it can boil you alive! "Fun" related story. For a year or so in grad school I was in charge of the microwave and radar lab. The safety folks came for an annual inspection, and I toured them a
177.
by mjb 4y ago
Related to tracking radars, conical scan and monopulse tracking has got to rank among the best brilliantly simple ideas: https://en.wikipedia.org/wiki/Monopulse_radar A monopulse tracking radar can track a target withi
178.
by mjb 4y ago
"Beamforming" (and the author is right to be skeptical of that term) is some really cool magic. My understanding of the history is that a lot of the technology comes from military radars. Development there was driven by power and
179.
NoSQL: The Baby and the Bathwater(brooker.co.za)
3 points by mjb 4y ago|2 comments
180.
by mjb 4y ago
Yes, indeed. We talk about it here https://cacm.acm.org/magazines/2015/4/184701-how-amazon-web-... (or here https://lamport.azurewebsites.net/tla/formal-methods-amazon.... if you can&#x2

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