HP Matrix Operating Environment Software - Manual (Page 102)

H Units of measurement
Storage is reported in bytes. There are three ways that storage vendors' management software
reports storage capacity: binary units, decimal units, and binary with decimal units. Binary units
have been proposed by the International Electrotechnical Commission (IEC) and adopted by the
United States National Institute of Standards and Technology (NIST). Decimal units are part of the
International System of units (SI). Binary with decimal units are used as a matter of historical
precedent by many software and hardware vendors (sometimes called the customary binary prefix).
SPM converts the capacity of all storage devices to a common format according to a user preference.
Because other software may use a different format than the one specified in the SPM preferences
dialog, it is important for users of SPM to be aware of the units of measurement in use and how
they differ. Binary units are indicated by the following abbreviations within SPM: KiB, MiB, GiB,
and TiB. Decimal units or binary with decimal units are indicated by the following abbreviations
within SPM: KB, MB, GB, TB. When using binary units, differences between the various units of
measure are computed using powers of two. The table below illustrates the three different systems
used for units of measurement.
Binary with Decimal Units Decimal Units (SI) Binary Units (IEC)
2^10 bytes = 1KB 10^3 bytes = 1KB 2^10 bytes = 1KiB
2^20 bytes = 1MB 10^6 bytes = 1MB 2^20 bytes = 1MiB
2^30 bytes = 1GB 10^9 bytes = 1GB 2^30 bytes = 1GiB
2^40 bytes = 1TB 10^12 bytes = 1TB 2^40 bytes = 1TiB
The Matrix Operating Environment currently uses decimal units. SPM users may choose to use any
of the three units of measurement, but it may be advisable to choose a unit of measurement that
minimizes the number of conversions to be performed in working with SPM.
102 Units of measurement