try {
synchronized (markLock) {
// While we have records in the journal.
while ((pos = journal.getNextRecordLocation(pos)) != null) {
Packet packet = journal.read(pos);
byte[] buffer = packet.sliceAsBytes();
if (buffer[0] == DELETE_BYTE) {
UUID id = new UUID(buffer, 1);
results.remove(id);
unusedMarks.add(pos);
RecordLocation loc = (RecordLocation)marks.remove(id);