Tim Potter

How your email finds me.

Announcing the launch of our Differential Equations course! Please visit the DE course page for the description and contents here: mathacademy.com/courses/differ…

@fauxtakufoxtaco @iky_fwjett This is news to me!

@iky_fwjett For people confused on "honk if you like pizza" the joke is that if the driver ever inconveniences you and you need to honk at him, it's going to seem as though you like pizza instead of being annoyed

The fact you can talk to your library would have seemed bizarre 10 years ago; today it seems bizarre that you can't

@i2cjak I can do through-hole resistors.

if you can place an 0402, you are basically a software engineer if you can place an 0201, you are a LOW TIER electrical engineer if you can place an 01005... I kneel...

@Jordan_W_Taylor @snurosnare @CalumDouglas1 The Algebraist probably the most fun.

@snurosnare @CalumDouglas1 Good choices all! Consider Phlebas was my first introduction to the Culture books, but on reflection Player Of Games is probably a better opening read and the most fun. Use Of Weapons is beautiful but not 'fun': Like a jewelled torture implement. My fave is Look To Windward.

I was influenced @CalumDouglas1 @Jordan_W_Taylor

@DJSnM Double granny knots are fine though.

I once found a NASA document with specifications for aerospace grade knots, noting that granny knots are specifically forbidden on spaceflight hardware.

@CJHandmer A friend built a Beowulf cluster back in the day and loading it up too much caused caps to melt off desktop-grade motherboards.

@CJHandmer When peak load = average load.

Currently making a streamable version of this available online. Uploading at 10 GB/hour from two different connections. So, at this rate, about a week more to go... I read stories about early Google server farms catching fire and I just want to say that in my whole life I've experienced computer hardware failure 8 times and 7 of them have been during the ~1% of my life when I worked on this project.

@i2cjak Enjoy! I probably wrote 10k lines of code while babies were sleeping.

baby sleeping on his own i can finally work at night.

When your code is in really bad condition but somehow still works.

Age verification going about as well as you would expect.

@patio11 This is such a great, if counterintuitive, view on the world of processes.

The process is very good at extracting truck -> palette -> carton -> ream but it does not have a pathway which goes in the other direction and it is cheaper to just eat misdeliveries than engineer and operate that pathway (across great majority of SKUs).

A vignette: Amazon driver: *delivers a pile of packages* Dad, who lives with us: Do you know the person these are addressed to? Me: Nope. Address is wrong, too. Likely a misdelivery. Dad: These are probably Christmas presents. I will call Amazon and get this straightened out.

@justinskycak Four months in and finally starting to get the low-stakes part. Scoring 100% on a quiz is a buzz, but it’s dawning on me that they are gently probing to find your weaknesses, and that’s way more valuable.

Frequent, low-stakes quizzes are such a powerful learning tool.

@ElecNotes Sorry, that was an attempt at a joke. Hey, I enjoyed your superhet radio book - finding the history part of things fascinating.

@timothypotter I didn’t know that.

1N5822 Schottky Diode The 1N5822 is the highest voltage rating diode in the series 1N5820 - 1N5822 series. These diodes boast a current capability of 3A which is ideal for many applications, and a maximum reverse voltage of 40V. The diode also has a guard ring incorporated into the structure to make the diode more resilient to breakdown and along with this it also gives very low conduction losses and a low forward voltage drop. The 1N5822 provides extremely fast switching and enables high frequency operation as a result of the Schottky structure. In addition to this, the diode offers a high forward surge current capacity, and it also offers a higher reverse voltage than the 1N5820. The diode is stocked by a variety of component distributors including: Arrow Electronics VericalFarnell Electronics DigiKey Mouser Electronics and many others. Check out the performance parameters as well as the distributor stock and prIcing: electronics-notes.com/articles/compo…

@psviderski Oh neat - the heartbeat idea is cool.

Today I’m solving a classic distributed systems problem: how to reliably stream logs from multiple replicas in chronological order? Surprisingly, none of the mainstream container tools do this. docker service logs, kubectl logs, stern, kubetail, k9s - they all just interleave streams as they arrive. The standard workaround is to pipe through | sort 🙃 To do it properly, you can't immediately print a log entry because a slower stream might have an earlier timestamp that hasn't arrived yet. You need to know when it's "safe" to print. Here's how I'm solving this for the new 'uc logs' command. You need two things: 1. Low watermark Track the minimum timestamp across all log streams and safely print buffered logs with timestamps below this watermark. > watermark = min(latest_timestamp for each stream) > sort and print all buffered logs where timestamp < watermark 2. Heartbeat timestamps What if a container becomes quiet? The entire stream gets stuck because the watermark wouldn’t advance. The solution is to periodically send empty heartbeat entries with the current timestamp from the servers. This is a promise: "I have no logs older than this" This lets the client advance the watermark immediately instead of blocking the output. 500ms–1s interval works well in practice. What about unsynchronised clocks? Not much you can do without making things messy. Just detect it, warn the user, and call it a day.

@jorandirkgreef @amr_hedeiwyy Wow - after all these years it still amazes me that there can be serious bugs in code that has probably been running for millions of hours.

Yes, for increased performance (and safety) e.g. TigerBeetle can run directly on the raw block device without a filesystem. Filesystems introduce risk, they have bugs (e.g. XFS had a rare misdirected I/O bug last year that would sometimes write to the wrong place on disk). They can also get into read only mode, and cause an outage, if they hit an Latent Sector Error, whereas e.g. TB can detect and handle this, to repair and recover without impacting availability. These are advanced concepts, but then again, the DBMS is responsible to handle them and get this right.

Quick question to database folks, does the underlying file system matter in a DBMS? I'd guess it does, but how'd u decide which one is suitable? What are the tradeoffs? What's the thought process when choosing one? I've never seen any textbooks/papers talking about this topic.

@1llegalEngineer Linter rules are meant to be broken!

If I ever start a company I will make sure all employees have a criminal record for doing something cool

@RueNahcMohr The i960 was really fun to program in. It had such a simple instruction set which you could keep in your head and not have to break out any docs.

check out the silly old chips, what are these anyway? ;]