Patent ID: 7711709

Claim:
A method in a computer system for processing snapshot measures, the method comprising: dividing a metric into a set of volatile parts and a set of non-volatile parts; storing periodic snapshots of said set of volatile parts, wherein a time duration between a pair of periodic snapshots is fixed and predetermined; storing interval snapshots of said set of non-volatile parts, wherein an interval snapshot of said set of non-volatile parts is recorded only upon detecting a change in the state of at least one of said non-volatile parts; upon receiving a query for a snapshot fact of said metric at a specified time, performing the following for said set of volatile parts: identifying a most recent periodic snapshot of the set of volatile parts prior to the specified time; determining a first value of the metric from the identified most recent periodic snapshot; determining a second value of the changes to the metric that occurred since the most recent periodic snapshot and the specified time; summing the first value of the metric and the second value of the changes to the metric, thereby generating a summed value; and performing the following for said set of non-volatile parts: identifying an interval snapshot of said set of non-volatile parts whose time period encompasses the specified time; and determining a third value of the metric from the identified interval snapshot.