PerfIntervalCount64

• Base type Unsigned64

A gauge associated with a performance measurement in a previous 15 minute measurement interval. In the case where the agent has no valid data available for a particular interval, the corresponding object instance is not available and upon a retrieval request a corresponding error message shall be returned to indicate that this instance does not exist. Let X be an object with HCPerfIntervalCount syntax Let Y be an object with HCPerfCurrentCount syntax. Let Z be an object with HCPerfTotalCount syntax. Then, in a system supporting a history of n intervals with X(1) and X(n) the most and least recent intervals respectively, the following applies at the end of a 15 minute interval: - discard the value of X(n) - the value of X(i) becomes that of X(i-1) for n >= i > 1 - the value of X(1) becomes that of Y. - the value of Z, if supported, is adjusted. This count represents a non-negative integer, which may increase or decrease, but shall never exceed 2^64-1 (18446744073709551615 decimal), nor fall below 0. The value of an object with HCPerfIntervalCount syntax assumes its maximum value whenever the underlying count exceeds 2^64-1. If the underlying count subsequently decreases below 2^64-1 (due, e.g., to a retroactive adjustment as a result of entering or exiting unavailable time), then the value of the object also decreases. Note that this TC is not strictly supported in SMIv2, because the 'always increasing' and 'counter wrap' semantics associated with the Counter64 base type are not preserved. It is possible that management applications which rely solely upon the (Counter64) ASN.1 tag to determine object semantics will mistakenly operate upon objects of this type as they would for Counter64 objects. This textual convention represents a limited and short- term solution, and may be deprecated as a long term solution is defined and deployed to replace it.