Search results
Results From The WOW.Com Content Network
Rotational latency (sometimes called rotational delay or just latency) is the delay waiting for the rotation of the disk to bring the required disk sector under the read-write head. [22] It depends on the rotational speed of a disk (or spindle motor), measured in revolutions per minute (RPM).
Access time is the time delay or latency between a request to an electronic system, and the access being initiated or the requested data returned.. In computer and software systems, it is the time interval between the point where an instruction control unit initiates a call to retrieve data or a request to store data, and the point at which delivery of the data is completed or the storage is ...
Latency, from a general point of view, is a time delay between the cause and the effect of some physical change in the system being observed. Lag, as it is known in gaming circles, refers to the latency between the input to a simulation and the visual or auditory response, often occurring because of network delay in online games. [1]
All of the factors above, coupled with user requirements and user perceptions, play a role in determining the perceived 'fastness' or utility, of a network connection. The relationship between throughput, latency, and user experience is most aptly understood in the context of a shared network medium, and as a scheduling problem.
File system fragmentation is more problematic with consumer-grade hard disk drives because of the increasing disparity between sequential access speed and rotational latency (and to a lesser extent seek time) on which file systems are usually placed. [8] Thus, fragmentation is an important problem in file system research and design.
To reduce the seek time and rotational latency, data are transferred to and from disks in large contiguous blocks. Sequential or block access on disks is orders of magnitude faster than random access, and many sophisticated paradigms have been developed to design efficient algorithms based on sequential and block access.
Major page faults on conventional computers using hard disk drives can have a significant impact on their performance, as an average hard disk drive has an average rotational latency of 3 ms, a seek time of 5 ms, and a transfer time of 0.05 ms/page. Therefore, the total time for paging is near 8 ms (= 8,000 μs).
Seek time is a measure of how long it takes the head assembly to travel to the track of the disk that contains data. Rotational latency is incurred because the desired disk sector may not be directly under the head when data transfer is requested. Average rotational latency is shown in the table, based on the statistical relation that the ...