The time a program or device takes to locate a single piece of information and make it available to the computer for processing. DRAM (dynamic random access memory) chips for personal computers have access times of 50 to 150 nanoseconds (billionths of a second). Static RAM (SRAM) has access times as low as 10 nanoseconds. Ideally, the access time of memory should be fast enough to keep up with the CPU. If not, the CPU will waste a certain number of clock cycles, which makes it slower.
Note, however, that reported access times can be misleading because most memory chips, especially DRAM chips, require a pause between back-to-back accesses. This is one reason why SRAM is so much faster than DRAM, even when the reported access times are equivalent; SRAM doesn’t require any refreshes, so there is no pause between back-to-back accesses. A more important measurement of a chip’s speed, therefore, is its cycle time, which measures how quickly two back-to-back accesses can be made.
Access time is also frequently used to describe the speed of disk drives. Disk access times are measured in milliseconds (thousandths of a second), often abbreviated as ms. Fast hard disk drivesfor personal computers boast access times of about 9 to 15 milliseconds. Note that this is about 200 times slower than average DRAM.
The access time for disk drives includes the time it actually takes for the read/write head to locate a sector on the disk (called the seek time). This is an average time since it depends on how far away the head is from the desired data.
In information technology, accounting is the process of keeping track of a user’s activity while accessing a network’s resources, including the amount of time spent in the network, the services accessed while there and the amount of data transferred during the session. Accounting data is used for trend analysis, capacity planning, billing, auditing and cost […]
- Accounting Software
A class of computer software, or program that helps accounting professionals mange accounts and perform accounting operations. The simplest accounting programs, sometimes called personal finance managers, are single-entry systems that automate tasks such as check writing and record keeping.
In channel partner terminology, accrual is a financial stipend that is provided to the sales channel by the vendor or manufacturer. The accrual amount is a usually a percentage of the invoiced price of items sold to the channel partner over a set period of time (e.g. a percentage of the previous six month’s sales).
- achromatic lens
In digital photography, achromatic is the term used to describe a camera lens system that is corrected for chromatic aberration, a defect in some optical lens systems that adds false color to images. Chromatic aberration is corrected by the achromatic lens as it brings two colors to the same focus. See chromatic aberration.
- Active Directory Service Interfaces
Active Directory Service Interfaces (ADSI) enable systems administrators and developers of scripts or C/C++ applications to easily query for and manipulate directory service objects. Active Directory Service Interfaces abstract the capabilities of different directory services from different network vendors to present a single set of directory service interfaces for managing network resources. Administrators and developers […]