This is a set of bits giving information on the status of this entry of the perfControlTable. The meaning of the individual bits is as follows: bit name Description 0 busy This bit is one if there is a DSL interface or V5 link referencing this perfControlEntry through a dslInterfacePerfControlIndexOrZero or a v5LinkPerfControlIndexOrZero value. This indicates that this perfControlEntry is busy, and its perfControlIndex value cannot be used in another DSL interface or V5 link. If the ...PerfControlIndexOrZero of the referencing interface or link is set to zero, this bit is also set to zero to show that this perfControlEntry is no longer busy - it can be used in another interface or link. 1 offline Device is offline, data may be absent or out of date. This bit is 0 if the last attempt to get performance history data from the device succeeded. In this case, the data bit (see below) is also 1. This bit (offline) is 1 if the last attempt to get performance history data failed. In this case, if no data have been received from the device, the data bit is 0, and no perfDataEntries are associated with this perfControlEntry. If some data was received from the device before the device went offline, the data bit may be 1, but the data may be out of date. 2 data Data is present. If this perfControlEntry is active, busy, and the device is not offline, this bit is to 1, which indicates that the perfDataEntries associated with this perfControlEntry are present and can be read from the perfDataTable. 3 marked This perfControlEntry has been used recently. The sweeper periodically sweeps all perfControlEntries, deleting entries with 0 in this bit. For entries with 1 in this bit, the bit is set to 0. Reading perfDataEntries sets the marked bit of the associated perfControlEntries to 1.