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A database without dynamic memory allocation

from Notes on software development [alt+shift+b] in technology

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12th Oct 2022

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Transactions are a protocol

Transactions are not an intrinsic part of a storage system. Any storage system can be made transactional: Redis, S3, the filesystem, etc. Delta Lake and Orleans demonstrated techniques to make S3 (or cloud storage in general) transactional. Epoxy demonstrated techniques to make Redis (and any other system) transactional. And of course there's always good old Two-Phase Commit. If you don't want to read those papers, I wrote about a simplified implementation of Delta Lake and also wrote about a simplified MVCC implementation over a generic key-value storage layer. It is both the beauty and the burden of transactions that they are not intrinsic to a storage system. Postgres and MySQL and SQLite have transactions. But you don't need to use them. It isn't possible to require you to use transactions. Many developers, myself a few years ago included, do not know why you should use them. (Hint: read Designing Data Intensive Applications.) And you can take it even further by ignoring the transaction layer of an existing transactional database and implement your own transaction layer as Convex has done (the Epoxy paper above also does this). It isn't entirely clear that you have a lot to lose by implementing your own transaction layer since the indexes you'd want on the version field of a value would only be as expensive or slow as any other secondary index in a transactional database. Though why you'd do this isn't entirely clear (I will like to read about this from Convex some time). It's useful to see transaction protocols as another tool in your system design tool chest when you care about consistency, atomicity, and isolation. Especially as you build systems that span data systems. Maybe, as Ben Hindman hinted at the last NYC Systems, even proprietary APIs will eventually provide something like two-phase commit so physical systems outside our control can become transactional too. Transactions are a protocol short new post pic.twitter.com/nTj5LZUpUr — Phil Eaton (@eatonphil) April 20, 2025

20th Apr 2025 • 54 votes
Phil Eaton on Technical Blogging

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25th Mar 2025 • 77 votes
From web developer to database developer in 10 years

Last month I completed my first year at EnterpriseDB. I'm on the team that built and maintains pglogical and who, over the years, contributed a good chunk of the logical replication functionality that exists in community Postgres. Most of my work, our work, is in C and Rust with tests in Perl and Python. Our focus these days is a descendant of pglogical called Postgres Distributed which supports replicating DDL, tunable consistency across the cluster, etc. This post is about how I got here. Black boxes I was a web developer from 2014-2021†. I wrote JavaScript and HTML and CSS and whatever server-side language: Python or Go or PHP. I was a hands-on engineering manager from 2017-2021. I was pretty clueless about databases and indeed database knowledge was not a serious part of any interview I did. Throughout that time (2014-2021) I wanted to move my career forward as quickly as possible so I spent much of my free time doing educational projects and writing about them on this blog (or previous incarnations of it). I learned how to write primitive HTTP servers, how to write little parsers and interpreters and compilers. It was a virtuous cycle because the internet (Hacker News anyway) liked reading these posts and I wanted to learn how the black boxes worked. But I shied away from data structures and algorithms (DSA) because they seemed complicated and useless to the work that I did. That is, until 2020 when an inbox page I built started loading more and more slowly as the inbox grew. My coworker pointed me at Use The Index, Luke and the DSA scales fell from my eyes. I wanted to understand this new black box so I built a little in-memory SQL database with support for indexes. I'm a college dropout so even while I was interested in compilers and interpreters earlier in my career I never dreamed I could get a job working on them. Only geniuses and PhDs did that work and I was neither. The idea of working on a database felt the same. However, I could work on little database side projects like I had done before on other topics, so I did. Or a series of explorations of Raft implementations, others' and my own. Startups From 2021-2023 I tried to start a company and when that didn't pan out I joined TigerBeetle as a cofounder to work on marketing and community. It was during this time I started the Software Internals Discord and /r/databasedevelopment which have since kind of exploded in popularity among professionals and academics in database and distributed systems. TigerBeetle was my first job at a database company, and while I contributed bits of code I was not a developer there. It was a way into the space. And indeed it was an incredible learning experience both on the cofounder side and on the database side. I wrote articles with King and Joran that helped teach and affirm for myself the basics of databases and consensus-based distributed systems. Holding out When I left TigerBeetle in 2023 I was still not sure if I could get a job as an actual database developer. My network had exploded since 2021 (when I started my own company that didn't pan out) so I had no trouble getting referrals at database companies. But my background kept leading hiring managers to suggest putting me on cloud teams doing orchestration in Go around a database rather than working on the database itself. I was unhappy with this type-casting so I held out while unemployed and continued to write posts and host virtual hackweeks messing with Postgres and MySQL. I started the first incarnation of the Software Internals Book Club during this time, reading Designing Data Intensive Applications with 5-10 other developers in Bryant Park. During this time I also started the NYC Systems Coffee Club. Postgres After about four months of searching I ended up with three good offers, all to do C and Rust development on Postgres (extensions) as an individual contributor. Working on extensions might sound like the definition of not-sexy, but Postgres APIs are so loosely abstracted it's really as if you're working on Postgres itself. You can mess with almost anything in Postgres so you have to be very aware of what you're doing. And when you can't mess with something in Postgres because an API doesn't yet exist, companies have the tendency to just fork Postgres so they can. (This tendency isn't specific to Postgres, almost every open-source database company seems to have a long-running internal fork or two of the database.) EnterpriseDB Two of the three offers were from early-stage startups and after more than 3 years being part of the earliest stages of startups I was happy for a break. But the third offer was from one of the biggest contributors to Postgres, a 20-year old company called EnterpriseDB. (You can probably come up with different rankings of companies using different metrics so I'm only saying EnterpriseDB is one of the biggest contributors.) It seemed like the best place to be to learn a lot and contribute something meaningful. My coworkers are a mix of Postgres veterans (people who contributed the WAL to Postgres, who contributed MVCC to Postgres, who contributed logical decoding and logical replication, who contributed parallel queries; the list goes on and on) but also my developer-coworkers are people who started at EnterpriseDB on technical support, or who were previously Postgres administrators. It's quite a mix. Relatively few geniuses or PhDs, despite what I used to think, but they certainly work hard and have hard-earned experience. Anyway, I've now been working at EnterpriseDB for over a year so I wanted to share this retrospective. I also wanted to cover what it's like coming from engineering management and founding companies to going back to being an individual contributor. (Spoiler: incredibly enjoyable.) But it has been hard enough to make myself write this much so I'm calling it a day. :) I wrote a post about the winding path I took from web developer to database developer over 10 years. pic.twitter.com/tf8bUDRzjV — Phil Eaton (@eatonphil) February 15, 2025 † From 2011-2014 I also did contract web development but this was part-time while I was in school.

15th Feb 2025 • 57 votes
Logical replication in Postgres: Basics

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17th Jan 2025 • 95 votes
Picking up volleyball in NYC with Goodrec and New York Urban

I was so intimidated to go at first, but it is in fact easy and fun to start playing beginner volleyball in New York. The people are so friendly and welcoming that it has been easy to keep playing consistently every week since I started for the first time this August. It's been a great workout and a great way to make friends! The two platforms I've used to find volleyball games are Goodrec and New York Urban. While these platforms may also offer classes and leagues, I mostly use them to play "pickup" games. Pickup games are where you show up and join (or get assigned to) a team to play for an hour or two. Easy to go on your own or with friends. I'm not an expert! My only hope with this post is that maybe it makes trying out volleyball in New York feel a little less intimidating for you! Goodrec With Goodrec you have to use their mobile app. Beginner tier is called "social" on Goodrec. So browse available games until you find one at the level you want to play. You enroll in (buy a place in) sessions individually. Sessions are between 90-120 minutes long. They ask you not to arrive more than 10 minutes early at the gym. When you arrive you tell the gym managers (usually in a desk up front somewhere) you're there for Goodrec and the tier (in case the gym has multiple level games going on at the same time). Then you wait until the Goodrec "host" arrives and they will organize everyone into teams. Goodrec hosts are players who volunteer to organize the games. They'll explain the rules of the game (makes Goodrec very good for beginners) and otherwise help you out. Always say thank you to your host! New York Urban With New York Urban, pickup sessions are called "open play". There is no mobile app, you just use the website to purchase a spot in a session. The sessions are longer and cheaper than Goodrec. But there is no host; players self-organize. The options are more limited too. You play at one of four high schools on either a Friday night or on Sunday. And session slots tend to sell out much more quickly than with Goodrec. Big City Volleyball You can also check out Big City Volleyball but I haven't used it yet. Volo I haven't ever done Volo but I think I've heard it described as "beer league". That even some of the beginner tier sessions with Goodrec and New York Urban are more competitive. But also, Volo is built around leagues so you have to get the timing right. Goodrec's and New York Urban's pickup games make it easy to get started playing any time of year. Making friends It was super awkward to go at first! I went by myself. I didn't know what I was doing. I couldn't remember, and didn't know, many rules. I didn't have court shoes or knee pads. But the Goodrec host system is particularly great for bringing beginners in and making them feel welcome. You have a great time even if you're terrible. The first game I went to, I tried to hang out afterward to meet people. But people either came with their SO or with their friends or by themselves so they all just left immediately or hung out in their group. So you can't just go once and expect to make friends immediately. But if you keep going at the same place and time regularly week over week, you'll see familiar faces. Maybe half the people I play with each week are regulars. If you're friendly you'll start making friends with these people and eventually start going out to bars with them after the games. Improving Even if you find yourself embarrassingly bad at first, just keep going! I'm 29, 6'1, 190lbs and from observation the past 5 months, age, height, and weight have a very indirect relation to playing ability. Most of the people who play are self-taught, especially at the lower tiers I've played at. But some people played for the school team in high school or college. These people are fun to play with and you can learn a lot from them. Most people who are self-taught seem to watch YouTube videos like Coach Donny, helpful for learning how to serve, set, block, etc. Or they take "clinics" (classes) with Goodrec or other platforms. (I have no idea about these, I've never done them before.) At first I played 2 hours a week and I was completely exhausted after the session. Over time it got easier so I started playing 2-3 sessions a week (6-9-ish hours). With practice and consistency (after about 3-4 months), I started playing Intermediate tier with Goodrec and New York Urban. And I don't think I'll play Beginner/Social at all anymore. I still primarily play for fun and for the workout and to meet people. But it's also fun to get better! I played with one person much better than myself in an Intermediate session one time and he mentioned he will probably stop playing Intermediate and only play High Intermediate. He mentioned you get better when you keep pushing yourself to play with better and better players. Good advice!

26th Dec 2024 • 80 votes

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The classic console corner's CRT changeover

In the corner of the rear Floodgap lab sits a pile of classic game consoles. It used to look like this: Sega Dreamcast all the consoles here only came with NTSC RF output and date from the pre-flat panel TV era. That includes multiple Atari consoles (including the inevitable VCS, here a Darth Vader 2600), several Pong machines — including two Commodore units — with various chipsets, an Intellivision (as the rebadged Tandyvision One, my first) and a Bally Astrocade with lots of upgrades. It seems wrong to use them with a flat panel, and CRTs lag less. Plus, games with a light gun (here the Dreamcast and one of the Pong consoles) often rely on the CRT's rapidly scanning beam to know where they're pointed. So what do you do when the CRT TV goes bad? I should note that this isn't all the old school gaming fun in the house. In the commons next to the pinball machines are an Xbox 360 Slim and a PlayStation 2, and in the home theatre connected to the 3D projector is a PlayStation 3 since it has some stereoscopic titles. These might appear in future articles. But most of the rest are here. I bought this Panasonic Omnivision PV-M2035 from a friend at church in 1999 for $100 [about $200 in 2026 dollars]. He had no use for it, and the top of the plastic shell had been heat-warped by sitting in his car too long, but it worked, still had the remote, and was a suitably cheap TV for my unsuitably cheap studio apartment. I used it for local news and Friends with a set of rabbit ears, VHS movies, and speakers for playing music by connecting a CD player to the single rear input. When I moved to a less cheap 1-bedroom, it came along, and its flat top was flat enough to become a shelf for a DVD player. I got the Dreamcast from Fry's in 2001 after Sega discontinued it and managed to share the composite input between them. That apartment was my crashpad for about a decade before moving to the current orbiting HQ, whereupon I bought a passive-3D flat panel TV and moved the Omnivision to its current location in the back of the house. It shared the RF input between the Inty, and later the Atari 2600, and later still the Astrocade and various Pongs. At any one time there were at least four consoles always connected to it via switches and switchboxes, and I wired up an accessory port for more. plastic was broken and on these TVs that's pretty much the load-bearing part. When it arrived at the mailbox and I unpacked it, I could see the lower half had sandwiched right through the VCR slot, with visible PCB fragments and broken buttons; aside from the tube itself (ironically), the thing was a total loss. The seller nevertheless made good on the refund, to their credit, and I got to schlep it to the recycler. Overall, however, it had occurred to me that there were very few TVs sufficiently contemporary with the M2035 out there, which might be a hint about their general longevity. So, if I was going to be forced to buy a different Panasonic, then it might as well be a more recent one, and it should be one of the "triple play" units (i.e., TV, VCR, DVD) so that I could at least get rid of the external DVD player. Mission: Impossible '88 and '89 DVD sets, where the "in stereo" animation was even burned into the video stream.) not recording and thus impossible to watch many DVDs, for which the Sima CopyMaster was the cheapest solution: it simply blots out that portion of the vertical blank along with the pulses, which also has the side effect of sometimes stripping closed captioning (in the vertical blank as well), though DVDs with proper subtitles are of course unaffected. Later Sima devices could regenerate portions of the vertical blank for better quality, and Macrovision actually sued them over their products in 2005, but later settled. The mixer on the right was purchased literal decades ago at Radio Shack (more specifically a "Video Enhancer Stereo Audio Mixer") that I think we used for a Halloween display exactly once and then forgot about. Here it was used first as a cutoff switch, and second as a way to match the audio volume from the DVD player with the audio volume from the Dreamcast, which was also directly connected to the second rear Y-cable. This TV is mono, so the stereo channels from the audio mixer and the DC get merged using their own Y-connectors (also Radio Shack) before going into the Y-cable to the single line audio input. The video function isn't used here at all; it was just a audio mixer on the shelf I wasn't otherwise using. The DVD player is under the mixer and the CopyMaster, a cheapie Sony special that will only eject discs if it's in the mood or summarily threatened with violence. You already met this system when we adjusted the laser pickup and refurbished its rechargeable battery. you met the Tandyvision One (otherwise identical to the Mattel Intellivision Master Component, and manufactured by them as an OEM) when we installed a composite video modification and a front power-cutoff reset. I later upgraded it with an original Mattel Intellivoice speech synthesizer (Tandy never rebadged these) and a CuttleCart. But you haven't met the Bally on the bottom, officially introduced in 1978 as a game console and simple home computer, sold under various names such as the Bally Professional Arcade seen on early units, later the Bally Computer System badging here, and now collectively referred to under its final incarnation as the Astrocade. These machines were based around a 1.789MHz Z80 (half NTSC colourburst) combined with the same graphics hardware Dave Nutting Associates used for Midway's arcade games Gorf and Wizard of Wor, among others. Unfortunately, much of its theoretical graphics power went unrealized because it only has half the video memory of the arcade units (i.e., 4K) — and that's all the memory it has, so it has to interleave bits in the video memory to store BASIC programs, meaning only game ROMs can take full advantage. Still, that was enough to be solid competition for the likes of the Atari VCS and Fairchild Channel F, and it holds its own well against the slightly later Intellivision. does have is a doozy: the cooling vents are on the underside. These machines are very prone to overheating and can be easily damaged by it, which is why I use two foam struts to keep it off the carpet. The yellow label is for Astrovision, a separate enterprise that had been attempting to develop their own console. The (then) Bally Professional Arcade was selling poorly, though part of this was due to a tardy launch and Bally's weak retail presence, and Bally decided to sell off the consumer products division in 1979. Astrovision, unable to get their unit to market quickly, bought it in 1981 along with a limited license to the Bally name and reintroduced it at Winter CES 1982. Astrovision units are otherwise the same except for the badging and are the most common Astrocades today, though the company became another victim of the 1983 video game crash and went bankrupt shortly afterwards. Simultaneously, an Astrocade derivative merged with Bally's unfinished ZGRASS-100 expansion chassis was reworked into the Datamax UV-1 graphics generator, sold in small numbers until around 1982. the wall warts and power strips, and do a little spot vacuuming with the Roomba. out in spring. Gremlin's Blockade; and a simple calculator and screen paint toy ("Scribbling"). The display is a bit noisier than the Inty/Tandyvision, probably because of the difference in shielding, but still quite good. Videostak Video Game Center, which allegedly could accomodate a VCS, Intellivision or ColecoVision. The front decal is somewhat worn and the woodgrain veneer doesn't match the Vader VCS nearly as well, but it's still a fun-looking setup. Intellivision System Changer which has Atari 2600 hardware in an expansion box for the Intellivision II (useable on the original Inty with modification). It might be fun to explore the reputed irregularities between what is believed to be a VTI clone TIA in the System Changer and the slightly earlier Coleco Expansion Module 1 (and the related Coleco Gemini), and see how they differ in practice. Now for the Pong machines. These attach to the "accessory port" on the input switcher. The current Pong menagerie are mostly MOS 7600-based, MOS' own Pong-on-a-chip: two from Commodore themselves but PAL only using the MOS 7601 (the TV Game 2000K and TV Game 3000H), plus two MOS 7600 (NTSC) systems, a Coleco Telstar Gemini, not to be confused with the Coleco Gemini or Coleco Telstar, and an Allied Leisure Name of the Game II, possibly the earliest use of the chip in NTSC regions. We'll play the Name of the Game II and Telstar Gemini below. These will be consoles for another day, but I also have a boxed Atari Video Pinball, an "honorary" Pong machine though it plays several other games, and a boxed Atari Ultra Pong Doubles, which we had before we got the Tandyvision, but I don't ever recall it working fully and it later failed to power up and got thrown away, so this is a replacement. My least favourite of the Pongs here (I really only picked it up because it was cheap) is a 1977 Magnavox Odyssey 3000. The 3000 is basically an upmarket Odyssey 2000 with proper handheld controllers, but otherwise the same me-too AY-3-8500 Pong-on-a-chip generating the same black-and-white display. Allied Leisure Name of the Game II is a two-player Pong based on the MOS 7600-001. This chip notionally contains three field games (a tennis game, a "goal" game usually billed as either soccer or hockey, and a racquetball game) and a skeet shooter, but the racquetball game can be put into a single player mode by setting it to "four" players and the NotG2's switch triggers this mode in place of the skeet shooter. It was noisy on the other TV and it's noisy here, possibly because it has its own internal RF switchbox, but it plays fine. Coleco Telstar Gemini, an MOS 7600-004 system. This has two "pinball" variants (with flippers and moveable Pong paddles, so it's still a Pong of sorts) and two shooting gallery variants involving shooting a deformed bear sprite. The light gun connector is the same as the Coleco Telstar, so I borrowed the gun from that. sing along with The Offspring. But the output looks crisp through the rear jacks, the sound is proper stereo, and we now have front inputs I can use for something else without rigging a whole bunch of Y-adapters again. Plus, if the Telstar Gemini's gun works, it's all but guaranteed the Dreamcast's does. am likely to play some Video Pinball, and in its box that's easy to move, so that can go on top of the 2600 and the NotG and Telstar Gemini can sit next to it. The old TV is out in the garage and as I have time I'll extract its circuit boards and go over them more thoroughly, since I had a lot of good times with that television and it would be nice to fix. If I do, I'll write it up here, since it's an actual old VCR. Meanwhile, I have some possible projects in mind for the Tandyvision and Astrocade, and maybe some mods to go in the VCS, and you can read about those in future articles too. In the end, with the new TV all set up, the 1980s can live again in my rear office. Or, as my wife likes to point out, they never actually died there either.

yesterday • 1 votes
Nazi Literature in the Americas

Learn by fire.

2 days ago • 1 votes
iPhone Duo early review

By a mile, the iPhone Duo has garnered more questions about what I think about it than any other phone I’ve ever had. It’s clearly a phone that has people intrigued, so I thought I’d jot down some loose, unorganized thoughts about what I think about it after about ten days. If I could sum all my thoughts up into one word, it’d simply be “fun”. I think for the vast majority of people, myself included, the iPhone 18 Pro is a more practical phone that through scientific analysis you’d likely even find a better phone. Even if they were priced the same, its package is more traditionally comfortable and ergonomic, with a better quality main camera, a helpful telephoto camera, a screen that’s more practical to use more of the time, a better biometric system (Face ID versus Touch ID) and a more established software experience. But damn if the iPhone Duo isn’t fun. Phones have been downright boring for so long. Incredible technology, lovely apps, but the hardware has been a bit slow moving since the iPhone X. Maybe that’s why I jumped onto the iPhone Air so readily. Even that slight departure from “black slab of glass” to “a dramatically thinner black slab of glass” was exciting versus what we’ve grown accustomed to. So I pick up the Duo, and it’s kinda just exciting to hold a phone for the first time in ages. Maybe that’s a honeymoon period and after a few months I’ll be over it. Maybe everyone who tries a folding phone for the first time experiences this. And to be clear, it’s not just all raw novelty. The fun aspect is fueled by having an absolutely incredible inner screen that fundamentally transforms what a phone is and can be. In addition, support the Apple Pencil has turned out to be phenomenally handy for me to be able to jot down quick thoughts and notes. For downsides, Touch ID is objectively worse than Face ID, but honestly, I don’t mind it as much as I expected I would. The smaller camera sensor than the Pro series phones is still decidedly great (rumors were it was a 17e size which was not correct, it’s the size of the normal 17’s). Software support gets better by the day, though iOS on the Duo is still decidedly a bit buggy at times. Other random thoughts Touch ID is objectively worse than Face ID, but honestly, I don’t mind it as much as I expected I would, previewing notifications is where I miss it the most After getting used to having a single speaker in the iPhone Air for a year, having stereo (not to mention great sounding) speakers is amazing The FaceTime camera on the inside is indeed not great for selfies/photography but honestly perfectly acceptable for FaceTime, and I’d definitely prefer this solution over a cutout on the inside so I’m happy! It definitely has a heavy feel to it, but it’s nothing honestly that bothersome A lot of the reviews said something to the effect of “the crease is practically invisible” and while I don’t really mind it or anything I definitely would disagree with that statement, you can see it a fair bit even with light content The hinge is a bit harder to open than I expected, I’ve found the secret is don’t pry from the middle of the side, instead put a thumb near the top and bottom (also helps prevent pressing Camera Control instead which I was doing all the time). I imagine this is necessary to have it be able to stop at arbitrary angles once open (which I do like) and hopefully it loosens up a bit with more use, but playing with Android foldables at Best Buy I did find their hinge easier to open I am really split on the inner, nano texture screen. It definitely helps reflections, has a neat look to it, and is super nice to draw on with the pencil, but it’s significantly less vibrant than the outer display which to my eyes looks a fair bit nicer. I think they made the right decision ultimately but it’s definitely not a zero-compromise solution. I was considering nano texture on my next MacBook but after this I think I’ll stick with glossy. My glass half full take with the Duo for now though is that we get two really cool screens to play with The outer screen is awesome for taking photos, unlike taller iPhones, your viewfinder fills the screen completely so it’s the largest feeling viewfinder I’ve used on a phone I miss the action button, nice little launcher for ChatGPT/Claude depending on which month it is Battery life is downright phenomenal versus my iPhone Air and 15 Pro (two devices admittedly not known for having great battery life) So, I don’t think the Duo is for most people who either don’t care much about phones, or care a lot about having the perfect phone, but for a decent amount of people in the middle I think the Duo represents a fundamentally different experience, that’s a ton of fun, and I’m excited to be excited about a phone again. (But, Apple, please figure out a way to add a telephoto lens.)

3 days ago • 1 votes
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