L9449: CELL_LLC_TX_UP_GPRS_BKGND_LLC_PDU_TRANS_DURATION
This measurement provides the total transmission duration of all the uplink GPRS background services in a cell in a granularity period.
ms.
Every time the transmission of the background service is complete on the uplink GPRS TBF, the transmission duration is used as the transmission duration of the uplink GPRS TBF background service. In a granularity period, the total transmission duration of all background services on the uplink GPRS TBFs is used as the value of the counter.
This is an original counter without involving any formula.