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Nikita Bier, X's head of product, said in a post on Monday that "[m]any videos from top accounts are simply stolen from other users, sometimes 5 years after they originally went viral," while noting that videos on the platform "make up close to half the impressions on X." According to Bier, X is launching a […]
Ars analysis suggests the 9-year-old console could keep selling for years.
Something on Pluto and one of Saturn’s moons, Titan, absorbs light in a way unexplained by anything in spectroscopic databases.
While the auto industry wrings its hands over the electric vehicle market, sweating details like aerodynamic efficiency and range anxiety, a new EV startup based in Lisbon, Portugal, is zagging in a different direction. Amble's new electric buggy won't impress anyone with its 0-60 time or its self-driving features (it has none). Instead, it takes […]
ABC is firing back at the Federal Communications Commission after the agency opened an investigation into The View's airtime of political candidates. In a letter to the FCC on Tuesday, ABC argues that the agency's actions pose a risk to editorial independence by targeting programs "perceived as unfriendly to the current administration," as reported earlier […]
Netflix is bringing 2- to 20-minute videos to its platform through new partnerships with digital publishers, including Rolling Stone and Variety.
Google is hosting its next Made by Google launch event for Pixel hardware on August 12th in New York City, according to an invitation sent by Google to The Verge. Unusually, the event is taking place in the evening: It'll kick off at 6PM ET that day. The email also includes a brief animation teasing […]
The T70S can be eligible for racing events or built to be road-legal.
From a massive DOGE data breach and the hacking of critical energy and water systems to the hack of an FBI surveillance system, here are the most damaging security incidents and data breaches of 2026.
If you want to (legally) watch Avatar Aang: The Last Airbender, it finally has a trailer and a July 25 release date.
With this update, users can start a task from their desk, get status updates on their phone, and pick up the finished output later — even if their laptop is closed.
Auto-organize files on your Mac now with MCP & CLI support Discussion | Link
It's early, but the plan is to reduce dependency on Nvidia and Huawei.
As part of the mass layoffs hitting Xbox, Doom developer id Software has laid off around 50 percent of its staff, according to Game Developer. One source claimed to the publication that the cuts equate to more than 90 redundancies. Another source said that id's QA department was significantly impacted. The report was published the […]
Claude Cowork now keeps working on tasks even after you close your laptop. It’s part of a larger push toward smartphone-controlled agents.
New Innovation Graph data shows global developer communities growing faster than ever, with collaboration reaching new highs across many economies. The post Q1 2026 Innovation Graph update: Open source collaboration is accelerating worldwide appeared first on The GitHub Blog .
Everyone knows Next.js is the default full-stack JavaScript framework in 2026. The job ads say so,...
We're back with another installment of the DEV Weekend Challenge ! If you missed the earlier editions, these are short-form, high-energy challenges designed to fit right into your weekend. We're giving you the heads-up now so you can clear your schedule! How It Works Our challenge prompt will be revealed at launch. Follow #weekendchallenge for updates. You can also keep an eye on the DEV Weekend Challenge page or look out for the official announcement post from the DEV Team . From there, you'll have the entire weekend to build, document, and submit your project. That's all there is to it! Because our community spans every timezone on the planet, we've set the window so that everyone around the world gets at least a full weekend to participate. Important Dates Launch Time: July 10 at 2:00 AM UTC Submissions Due: July 13 at 6:59 AM UTC Here's what that looks like across a few timezones: Timezone Launch Time (Local) Submissions Due (Local) PDT Thursday, Jul 9 at 7:00 PM Sunday, Jul 12 at 11:59 PM EDT Thursday, Jul 9 at 10:00 PM Monday, Jul 13 at 2:59 AM GMT Friday, Jul 10 at 2:00 AM Monday, Jul 13 at 6:59 AM CEST Friday, Jul 10 at 4:00 AM Monday, Jul 13 at 8:59 AM IST Friday, Jul 10 at 7:30 AM Monday, Jul 13 at 12:29 PM JST Friday, Jul 10 at 11:00 AM Monday, Jul 13 at 3:59 PM AEST Friday, Jul 10 at 12:00 PM Monday, Jul 13 at 4:59 PM While the window technically spans more than 48 hours, our goal is to ensure everyone has a full, uninterrupted weekend to work on their project regardless of where they live. What else is happening? Mark your calendars for the upcoming Summer Bug Smash . Bug Smash - Register Now We can't wait to see what you build!
HA dashboard cho Postgres replication: vì sao "có replica" không đồng nghĩa "đang HA", và cách để replica chết không âm thầm Streaming replication trong Postgres là một tunnel WAL từ primary sang standby: primary chạy một walsender cho mỗi standby, standby chạy một walreceiver nhận WAL và một startup process replay. Đau nhất trong vận hành không phải setup — mà là replica đã ngắt nhiều giờ mà không ai biết, tới lúc primary chết mới phát hiện HA thực ra là single-node từ tuần trước. HA dashboard là tập metric + alert được rút ra từ pg_stat_replication , pg_stat_wal_receiver , và pg_replication_slots để ép mọi trạng thái xấu — replica disconnect, replay đứng, slot pin WAL, sync standby biến mất — thành tín hiệu nhìn thấy được trước khi biến thành sự cố. Cơ chế hoạt động Trên primary, mỗi standby đang kết nối tạo ra một backend loại walsender — Postgres đọc WAL từ pg_wal/ (hoặc từ WAL buffers khi còn nóng) và stream qua replication connection. Trên standby, walreceiver nhận từng WAL record, ghi vào pg_wal/ local, fsync (tùy synchronous_commit ), rồi startup process apply record lên shared buffers — đây chính là replay. Bốn LSN xuất hiện trong luồng này và tương ứng với bốn cột trong pg_stat_replication : sent_lsn — byte cuối cùng primary đã gửi qua socket. write_lsn — byte cuối cùng standby đã write() vào OS page cache. flush_lsn — byte cuối cùng standby đã fsync xuống đĩa. replay_lsn — byte cuối cùng standby đã replay vào shared buffers (dữ liệu đã "thấy được" trên standby). Postgres docs quy định replay_lsn <= flush_lsn <= write_lsn <= sent_lsn <= pg_current_wal_lsn() — bốn "vạch" này chính là bốn nhịp của lag. Ba cột write_lag , flush_lag , replay_lag (kiểu interval ) là thời gian mà standby chậm hơn primary tương ứng với ba mốc write/flush/replay — được đo qua feedback message định kỳ từ standby. -- Trên primary: bức tranh đầy đủ cho một HA dashboard SELECT application_name , client_addr , state , -- streaming | catchup | startup | backup | stopping sync_state , --
WAL: vì sao Postgres bắt buộc ghi log trước data file, và lý do pg_wal/ đầy đĩa làm cluster ngừng nhận write WAL (Write-Ahead Log) là cơ chế durability lõi của Postgres: mọi thay đổi đối với heap, index, free-space map, visibility map đều phải được ghi xuống WAL và fsync trước khi data file tương ứng được phép flush ra đĩa . Nguyên tắc này, mô tả trong Postgres docs chương "Reliability and the Write-Ahead Log", là cái cho phép một transaction đã COMMIT thoả ACID-D dù OS crash hoặc mất điện ngay sau đó. Dev gặp WAL trong việc thật không phải vì cú pháp khó: gặp khi pg_wal/ đầy đĩa do một replication slot bị quên dọn, Postgres dừng nhận write với PANIC: could not write to file ... No space left on device , hoặc khi crash recovery sau OOM kéo mười mấy phút làm health check fail và load balancer cắt traffic. Cơ chế hoạt động Postgres không ghi thẳng vào data file mỗi khi có INSERT / UPDATE . Trang 8KB (heap page, index page) sống trong shared_buffers ; mỗi thay đổi tạo ra một WAL record mô tả delta đó (record type, relfilenode, block number, payload), append vào wal_buffers — một vùng shared memory nhỏ trước khi xuống đĩa. Tại thời điểm COMMIT , backend gọi XLogFlush() để write + fsync WAL tới hết byte chứa commit record; chỉ sau khi fsync trả về, Postgres mới ghi commit bit vào pg_xact và reply OK về client. Data page bẩn ở lại trong shared_buffers ; checkpointer sẽ flush chúng ra data file sau, không gắn với từng commit. WAL được tổ chức thành segment file kích thước cố định trong $PGDATA/pg_wal/ , mặc định 16MB mỗi segment (cấu hình lúc initdb --wal-segsize ). Vị trí trong WAL là LSN (Log Sequence Number) — số 64-bit, in dạng XXXX/XXXXXXXX , thực chất là byte offset từ đầu WAL của cluster. LSN tăng đơn điệu và là "đồng hồ" duy nhất Postgres tin cậy cho thứ tự ghi. -- Quan sát LSN tiến lên sau mỗi ghi SELECT pg_current_wal_lsn (); -- vd: 0/1A2B3C40 INSERT INTO t SELECT g FROM generate_series ( 1 , 1000 ) g ; SELECT pg_current_wal_lsn (); -- 0/1A2BE018 SELECT pg_wal_ls