In a method for reclaiming space occupied by an expired variable record in a non-volatile record storage, a reclaim state data that includes a state of a reclaim operation is maintained. In addition, the state of the reclaim operation is marked to indicate a progress of the reclaim operation at a plurality of stages of the reclaim operation. The reclaim operation is implemented by sliding, one section at a time, the data in a first direction along the plurality of sections and by sliding, one section at a time, the variable records, excluding the expired variable record, in a second direction along the plurality of sections, to thereby remove the expired variable record.