Access time is the time delay or latency between a request to an electronic system, and the access being completed or the requested data returned
In a computer and software systems, it is the time interval between the instant at which an instruction control unit initiates a call to retrieve data or a request to store data, and the instant at which delivery of the data is completed or the storage is started. Note that in distributed software systems, access time or latency) should be measured through '99th percentile.[1]