 In this sense, the terms "disk cache" and "cache buffer" are misnomers; the embedded controller's memory is more appropriately called "disk buffer".Note that disk array controllers, as opposed to disk controllers, usually have normal cache memory of around 0.5–8 GiB.When a disk's controller executes a physical read, the actuator moves the read/write head to (or near) the correct cylinder, after some settling and possibly fine-actuating the read head begins to pick up track data, and all is left to do is wait until platter rotation brings the requested data.