system/Cache/Handlers/MemcachedHandler.php
public function increment(string $key, int $offset = 1)
	{
		if (! $this->config['raw'])
		{
			return false;
		}

		$key = $this->prefix . $key;

		return $this->memcached->increment($key, $offset, $offset, 60);
	}
public function increment(string $key, int $offset = 1)
	{
		if (! $this->config['raw'])
		{
			return false;
		}

		$key = $this->prefix . $key;

		return $this->memcached->increment($key, $offset, $offset, 60);
	}
Performs atomic incrementation of a raw stored value.

@param string  $key    Cache ID
@param integer $offset Step/value to increase by

@return mixed