When values don’t change between requests (unlike static variables), Drupal’s caching system is a great, simple way to reduce the workload on your site and provide a flexible way to configure the storage duration of this data. Using just our handy cache_get() and cache_set() functions, we can implement an elegant solution to increasing performan…

Drupal cache.php

//First, let’s analyze the cache_set() parameters -

<?php
function cache_set($cid, $data, $bin = 'cache', $expire = CACHE_PERMANENT) {
  /* ... */
}
?>
//Example #1 (using a simple cache)

<?php
  $value = cache_get('cache_key');
  if (FALSE == $value) {
    // generate $value
    cache_set('cache_key', $value);
  }
?>
//Example #2 (creating your own cache)

<?php
  /* @file my_module.install */
  function my_module_schema() {
    $schema['cache_my_cache'] = drupal_get_schema_unprocessed('system', 'cache');
    $schema['cache_my_cache']['description'] = 'A cache table for my module.';
    return $schema;
  }
?>
<?php
  /* @file my_module.module */
  function my_module_flush_caches() {
    return array('cache_my_cache');
  }
?>