// Uncached model call
$this->blog_m->getPosts($category_id, 'live');

// cached model call
$this->cache->model('blog_m', 'getPosts', array($category_id, 'live'), 120); // keep for 2 minutes

// cached library call
$this->cache->library('some_library', 'calcualte_something', array($foo, $bar, $bla)); // keep for default time (0 = unlimited)

// cached array or object
$this->cache->write($data, 'cached-name');
$data = $this->cache->get('cached-name');

// Delete cache
$this->cache->delete('cached-name');

// Delete all cache
$this->cache->delete_all();

// Delete cache group
$this->cache->write($data, 'nav_header');
$this->cache->write($data, 'nav_footer');
$this->cache->delete_group('nav_');

// Delete cache item
// Call like a normal library or model but give a negative $expire
$this->cache->model('blog_m', 'getPosts', array($category_id, 'live'), -1); // delete this specific cache file