<?php

require_once 'vendor/autoload.php';

use Symfony\Component\Cache\Adapter\FilesystemAdapter;

// works:
$cache = new FilesystemAdapter('foo-namespace');
$keys = range(0, 999);
foreach ($keys as $key) {
    $cacheItem = $cache->getItem((string) $key);
    $cacheItem->set('value: ' . $key);
    $cache->save($cacheItem);
}
echo $cache->getItem('25')->get() . PHP_EOL; // "value: 25"

// doesn't work:
$cache = new FilesystemAdapter('xyz-namespace');
$keys = range(0, 1000);
foreach ($keys as $key) {
    $cacheItem = $cache->getItem((string) $key);
    $cacheItem->set('value: ' . $key);
    $cache->save($cacheItem);
}
echo $cache->getItem('25')->get() . PHP_EOL; // "value: 525"

// works:
$cache = new FilesystemAdapter('xyz-namespace');
$keys = range(0, 1000);
foreach ($keys as $key) {
    $cacheItem = $cache->getItem((string) $key);
    $cacheItem->set('value: ' . $key);
    $cache->save($cacheItem);
}
echo $cache->getItem('25')->get() . PHP_EOL; // "value: 25"