What are the main tasks that caching helps to solve in systems?

Caching in systems helps solve several key tasks:

• Speeding up data access: frequently used data is stored in fast access memory (RAM, local disk), reducing response time.
• Reducing load on data sources: decreases the number of requests to databases or external services, improving overall performance.
• Optimizing resource usage: saves network traffic and computational resources.
• Increasing fault tolerance: in case the data source is temporarily unavailable, the cache can serve as a backup.

An example in Go using a simple map-based cache:

package main

import (
    "fmt"
    "sync"
)

type Cache struct {
    mu    sync.RWMutex
    store map[string]string
}

func NewCache() *Cache {
    return &Cache{store: make(map[string]string)}
}

func (c *Cache) Get(key string) (string, bool) {
    c.mu.RLock()
    defer c.mu.RUnlock()
    val, ok := c.store[key]
    return val, ok
}

func (c *Cache) Set(key, value string) {
    c.mu.Lock()
    defer c.mu.Unlock()
    c.store[key] = value
}

func main() {
    cache := NewCache()
    cache.Set("user_1", "John Doe")

    if val, ok := cache.Get("user_1"); ok {
        fmt.Println("Cached value:", val)
    } else {
        fmt.Println("Value not found in cache")
    }
}

Thus, caching improves the efficiency and responsiveness of applications.