Habr4d ago

Buffer Pool и Clock-sweep: как мы боремся с cache pollution и p99 latency

Один аналитический запрос способен испортить p99 latency всего OLTP-трафика — на время, пока горячий рабочий набор не прогреется заново с диска. Это cache pollution, и с ним рано или поздно сталкивается любая СУБД с честным LRU. Разбираем, как мы решили эту проблему в нашем OLTP-движке: почему выбрали Clock-sweep вместо LRU, как BufferRing изолирует полные сканы от горячих данных, и почему no-steal — это не стилистический выбор, а требование корректности recovery. С кодом, инвариантами и честными оговорками про то, что ещё не сделано.

https://habr.com/ru/articles/1030822/

#buffer_pool #clock_sweep #cache_pollution #lru #eviction_algorithm #oltp #p99_latency #nosteal #wal #backpressure

Buffer Pool и Clock-sweep: как мы боремся с cache pollution и p99 latency

Один аналитик с одним SELECT count(*) FROM orders способен серьёзно ухудшить p99 latency всего OLTP-трафика. Пока скан читает таблицу страница за страницей, Buffer Pool заполняется «холодными»...

Хабр
HabrApr 13

dc.send(file) не существует: что на самом деле нужно для передачи файла в браузере

dc.send(file) не означает, что файл уже доставлен. Между отправкой и реальной доставкой – буфер, relay, запись на диск, ACK, reconnect и потерянный после refresh File. Разбираю шесть production-проблем WebRTC-файлообмена, которые обычно остаются за пределами туториалов.

https://habr.com/ru/articles/1022522/

#WebRTC #RTCDataChannel #TURN #SCTP #File_System_Access_API #backpressure #signaling #ACK #P2P #передача_файлов

dc.send(file) не существует: что на самом деле нужно для передачи файла в браузере

Рис. 1. dc.send(file) не означает, что файл уже доставлен. Самая опасная иллюзия в WebRTC-файлообмене выглядит примерно так: const dc = pc.createDataChannel('file'); for (let offset = 0; offset <...

Хабр
5021tipsMar 11

Removing particles (I) without #carhacking off the #OxygenSensors (Z & M) is 'ujinga' 🫣!
If You don't remove (I) but #carhack off (Z&M)🤔, at some point, engine is #backpressure f*ked😜 !

https://www.5021.tips/ujanja/emissions

Different configurations, but all can be tamed coz #HapaUjanjaTu #autorepairtips #5021tips #cartips #repairtips #ecurepair #dpf #EGR #adblue #ecu #carrepairtips #magari #autodiagnostika #OBD2

N-gated Hacker NewsJan 19
Moss insists you don’t squander your precious "back pressure" on lazy AI agents 🦾🔧, because nothing says #innovation like trusting robots to monitor themselves 🙄. Apparently, if you wrap them in enough structure and automated pats on the back, they’ll magically become error-free and tackle the tasks you can't be bothered with 🤖✨.
https://banay.me/dont-waste-your-backpressure/ #Moss #lazyAI #backpressure #automation #robotmonitoring #HackerNews #ngated
Don't waste your back pressure ·

Back pressure for agents You might notice a pattern in the most successful applications of agents over the last year. Projects that are able to setup structure around the agent itself, to provide it with automated feedback on quality and correctness, have been able to push them to work on longer horizon tasks. This back pressure helps the agent identify mistakes as it progresses and models are now good enough that this feedback can keep them aligned to a task for much longer. As an engineer, this means you can increase your leverage by delegating progressively more complex tasks to agents, while increasing trust that when completed they are at a satisfactory standard.

Hacker NewsJan 19

Don't waste your back pressure

https://banay.me/dont-waste-your-backpressure/

#HackerNews #BackPressure #Optimization #DeveloperTips #SoftwareEngineering #TechInsights

Don't waste your back pressure ·

Back pressure for agents You might notice a pattern in the most successful applications of agents over the last year. Projects that are able to setup structure around the agent itself, to provide it with automated feedback on quality and correctness, have been able to push them to work on longer horizon tasks. This back pressure helps the agent identify mistakes as it progresses and models are now good enough that this feedback can keep them aligned to a task for much longer. As an engineer, this means you can increase your leverage by delegating progressively more complex tasks to agents, while increasing trust that when completed they are at a satisfactory standard.

HabrJan 11

Очередь задач на Postgres: SKIP LOCKED + lease/heartbeat + backpressure (практический опыт)

Как сделать надёжную очередь задач без Rabbit/Kafka, используя только Postgres? Разбираю боевой паттерн: FOR UPDATE SKIP LOCKED для конкурентного забора, lease/heartbeat для возврата задач после падений и backpressure, чтобы воркеры не съели память.

https://habr.com/ru/articles/984102/

#PostgreSQL #очередь_задач #SKIP_LOCKED #FOR_UPDATE #lease #heartbeat #backpressure #atleastonce #idempotency #graceful_shutdown

Очередь задач на Postgres: SKIP LOCKED + lease/heartbeat + backpressure (практический опыт)

В какой-то момент на старте в нашем data-сервисе (известная в узких кругах аналитическая платформа для селлеров WB/Ozon «Таблички») стало возникать много фоновых работ: ETL‑сенсоры, сложные...

Хабр
N-gated Hacker NewsOct 29, 2025
🎓 Ah, the age-old struggle of backpressure: a term that just sounds like a gastrointestinal condition, yet it's somehow vital to your glorified #Excel sheet #leaderboard. 🏆 Let's pretend that #juggling packets and messages is the modern-day equivalent of scaling Everest, while we all know it's just a fancy way of saying "don't break the #internet, please." 🙄
https://blog.pranshu-raj.me/posts/backpressure/ #backpressure #safety #packet #modern #challenges #HackerNews #ngated
Backpressure in Distributed Systems | Systems & Sidequests

Understanding what it is, how to deal with it, where it's used and how I handled it in the real time leaderboard.

Hacker NewsOct 29, 2025

Backpressure in Distributed Systems

https://blog.pranshu-raj.me/posts/backpressure/

#HackerNews #Backpressure #Distributed #Systems #Scalability #Performance #Engineering #TechInsights

Backpressure in Distributed Systems | Systems & Sidequests

Understanding what it is, how to deal with it, where it's used and how I handled it in the real time leaderboard.

ThomasMILLOct 17, 2024
This is why most #aftermarket #high-performance #exhaust #systems have large-diameter #piping. 🏎️ The best way to go about this is to have an inch of diameter per 100 #HP. 📏 This way you also avoid reducing #backpressure to the point where no #performance #enhancements are gained. 🚫📉 https://livinginsydneycom.wordpress.com/2024/10/17/upgrading-to-a-performance-exhaust-how-the-pros-do-it/
Upgrading to a Performance Exhaust: How the Pros Do it

More often than not performance upgrades are related to the engine or a component in the engine bay. But performance isn’t only affected by your car’s powerplant and surrounding parts. …

Living in Sydney
ThomasMILLAug 12, 2024
The larger the piping is, the more air can pass through, which is why the majority of 💨🏎️ #Australian #exhaust #system #suppliers recommend getting a larger diameter system. A good rule of thumb is to have an inch of diameter for every 100HP. Going over this number can create too much #backpressure. 🔧 https://australianyouthlifestyle.wordpress.com/2024/08/12/buying-an-aftermarket-exhaust-a-newbies-guide/
Buying an Aftermarket Exhaust: A Newbie’s Guide

The exhaust system is the lungs of your car and without it, your vehicle would be unbearably loud and bad for the environment. Exhausts help take care of the fumes the engine generates while it&#82…

Australian Youth Lifestyle