// used, except in one case: whole-row deletes. In that case only,
// this timestamp is used by the RegionServer to create per-family
// deletes for that row. See HRegion.prepareDelete() for more info.
buf.writeLong(rpc.timestamp); // Timestamp.
buf.writeLong(RowLock.NO_LOCK); // Lock ID.
buf.writeByte(rpc.durable ? 0x01 : 0x00); // Use the WAL?
nfamilies_index = buf.writerIndex();
// Number of families that follow.
buf.writeInt(0); // We'll monkey patch this later.
}