mosmeh

Keyfront design documentation

This document outlines the design principles and architecture of Keyfront, a distributed proxy that allows better clustering solution for Redis/Valkey.

Motivation

Target use cases

Keyfront focuses on the use of Redis/Valkey as a large distributed cache, rather than as a primary database. In this use case, the following properties are desirable:

mosmeh

use std::{
    alloc::{GlobalAlloc, Layout, System},
    sync::atomic::{AtomicUsize, Ordering},
};

pub struct Allocator {
    inner: System,
    counter: AtomicUsize,
}

mosmeh

{
    "Dahina tabla": [1, 2.89, 4.95, 6.99, 8.01, 9.02],
    "Bayan tabla": [1, 2.0, 3.01, 4.01, 4.69, 5.63],
    "Red Cedar wood plate": [1, 1.47, 2.09, 2.56],
    "Redwood wood plate": [1, 1.47, 2.11, 2.57],
    "Douglas Fir wood plate": [1, 1.42, 2.11, 2.47],
    "uniform wooden bar": [1, 2.572, 4.644, 6.984, 9.723, 12],
    "uniform aluminum bar": [1, 2.756, 5.423, 8.988, 13.448, 18.68],
    "Xylophone": [1, 3.932, 9.538, 16.688, 24.566, 31.147],
    "Vibraphone 1": [1, 3.984, 10.668, 17.979, 23.679, 33.642],

mosmeh

use crossterm::{cursor, queue};
use std::io::{self, Write};
use std::sync::atomic::{AtomicBool, Ordering};
use std::sync::Arc;
use std::thread::{self, JoinHandle};
use std::time::Duration;

const DEFAULT_FRAMES: &str = "⠙⠹⠸⠼⠴⠦⠧⠇⠏";
const DEFAULT_INTERVAL: Duration = Duration::from_millis(50);

mosmeh

use serde::{Deserialize, Serialize};
use std::env;
use std::fs::File;
use std::io::Write;
use std::io::{BufRead, BufReader, BufWriter};

#[derive(Serialize, Deserialize)]
struct Article {
    id: String,
    title: String,

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unsafe fn slice_from_bytes<T>(bytes: &[u8]) -> &[T] {
    assert_eq!(0, std::mem::size_of::<T>() % std::mem::size_of::<u8>());
    assert_eq!(0, bytes.len() % std::mem::size_of::<T>());

    let ratio = std::mem::size_of::<T>() / std::mem::size_of::<u8>();
    let ptr = bytes.as_ptr() as *const T;
    let length = bytes.len() / ratio;

    std::slice::from_raw_parts(ptr, length)
}

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def eulerian_walk(nodes, start):
    tour = []

    def visit(n):
        if n in nodes:
            while nodes[n]:
                visit(nodes[n].pop())
        tour.append(n)
    
    visit(start)

mosmeh

#include <algorithm>
#include <iostream>
#include <vector>

using namespace std;

vector<int> dd(int y, const vector<int>& x) {
    vector<int> ret;
    for (int a : x) {
        ret.push_back(abs(a - y));

mosmeh

ASCIIでは

• A,C,G,Tの値は0x61,0x63,0x67,0x74なので，下位4bitを取り出すと1,3,7,4になり，すべて異なる値となる
• 大文字と小文字の値は0x20だけ違うため，下位4bitを取り出すと大文字と小文字は同じ値となる

→ 下位4bitだけ読むことでA,C,G,Tをcase-insensitiveに読める

int read_base(char c) {
    switch (c & 0xf) {
 case 'A' & 0xf: // 1

mosmeh

OBJS    := foo
VERSION := $(shell cat VERSION 2> /dev/null)
COMMIT  := $(shell git describe --always --tags --dirty 2> /dev/null)
CFLAGS  := $(if $(VERSION),-DFOO_VERSION=\"$(VERSION)\") $(if $(COMMIT),-DFOO_COMMIT=\"$(COMMIT)\")

.PHONY: all clean

all: $(OBJS)

clean: