| module Simulation | |
| # Clocks in a Linux system | |
| # ======================== | |
| # | |
| # A Linux system has two clocks: The hardware clock, and the system clock. | |
| # | |
| # The hardware clock, also known as RTC or real-time clock, is a physical | |
| # clock. This clock runs always, even when the system is shut down or | |
| # unplugged the clock keeps running because it has an independent source of | |
| # power, normally a lithium battery. See |
| n = 3004953 | |
| start = n/2 + 1 | |
| play = [*start..n, *1...start] | |
| while n > 1 | |
| play.shift | |
| play << play.shift if n.odd? | |
| n -= 1 | |
| end |
| // We use a circular double-linked list, and two pointers: one to the current player, | |
| // and another one to their target, the player across the circle. | |
| // | |
| // By using a cicular list, API is intuitive. | |
| // | |
| // By using a double-linked list, deletion is cheap. | |
| // | |
| // By maintaining both pointers in each turn, we avoid seeks. | |
| const ( |
| // Mandelbrot set generator from "Programming Rust", with I/O removed (the | |
| // original code writes a PNG file). | |
| use std::env; | |
| use std::str::FromStr; | |
| use num::Complex; | |
| fn main() { | |
| let args: Vec<String> = env::args().collect(); |
The Zeitwerk integration in Rails 6 has several parts.
First, we define a new configuration point Rails.configuration.autoloader here:
https://github.com/rails/rails/blob/master/railties/lib/rails/application/configuration.rb
and also set it to :zeitwerk in the 6.0 defaults.
Then, we define Rails.autoloaders here
| require "concurrent" | |
| class BatchWriter | |
| MAX_BATCH_SIZE = 100 | |
| TIMER_OPTS = { execution_interval: 1, timeout_interval: 1 }.freeze | |
| cattr_accessor :buffer | |
| self.buffer = [] | |
| cattr_accessor :mutex |
| Sidekiq.configure_server do |config| | |
| config.on(:startup) do | |
| BatchWriter.start_timer | |
| at_exit do | |
| BatchWriter.stop_timer | |
| BatchWriter.flush | |
| end | |
| end | |
| end |
| class LocationsJob < ApplicationJob | |
| queue_as :high_priority | |
| def perform(location) | |
| BatchWriter.push(location) | |
| end | |
| end |
| queue = Queue.new | |
| workers = Array.new(N) do | |
| Thread.new do | |
| while record = queue.pop | |
| # insert record | |
| end | |
| end | |
| end |
| records.each do |record| | |
| # insert record | |
| end |