diff --git a/libs/ardour/ardour/audioregion.h b/libs/ardour/ardour/audioregion.h
index b418a2c409..a13b817718 100644
--- a/libs/ardour/ardour/audioregion.h
+++ b/libs/ardour/ardour/audioregion.h
@@ -102,8 +102,7 @@ class AudioRegion : public Region
 		ReadOpsNone = 0x0,
 		ReadOpsOwnAutomation = 0x1,
 		ReadOpsOwnScaling = 0x2,
-		ReadOpsCount = 0x4,
-		ReadOpsFades = 0x8
+		ReadOpsFades = 0x4
 	};
 
 	virtual framecnt_t read (Sample*, framepos_t pos, framecnt_t cnt, int channel) const;
diff --git a/libs/ardour/ardour/audiosource.h b/libs/ardour/ardour/audiosource.h
index c9eb3bfc45..1d811bbfa3 100644
--- a/libs/ardour/ardour/audiosource.h
+++ b/libs/ardour/ardour/audiosource.h
@@ -67,10 +67,6 @@ class AudioSource : virtual public Source,
 	void set_captured_for (std::string str) { _captured_for = str; }
 	std::string captured_for() const { return _captured_for; }
 
-	uint32_t read_data_count() const { return _read_data_count; }
-	uint32_t write_data_count() const { return _write_data_count; }
-	void dec_read_data_count (framecnt_t);
-
 	int read_peaks (PeakData *peaks, framecnt_t npeaks,
 			framepos_t start, framecnt_t cnt, double samples_per_visual_peak) const;
 
@@ -131,9 +127,6 @@ class AudioSource : virtual public Source,
 	std::string         peakpath;
 	std::string        _captured_for;
 
-	mutable uint32_t _read_data_count;  // modified in read()
-	mutable uint32_t _write_data_count; // modified in write()
-
 	int initialize_peakfile (bool newfile, std::string path);
 	int build_peaks_from_scratch ();
 	int compute_and_write_peaks (Sample* buf, framecnt_t first_frame, framecnt_t cnt,
diff --git a/libs/ardour/ardour/butler.h b/libs/ardour/ardour/butler.h
index 9740099360..120f5871f4 100644
--- a/libs/ardour/ardour/butler.h
+++ b/libs/ardour/ardour/butler.h
@@ -51,9 +51,6 @@ class Butler : public SessionHandleRef
 	bool transport_work_requested() const;
 	void drop_references ();
 
-	float read_data_rate() const; ///< in usec
-	float write_data_rate() const;
-
 	framecnt_t audio_diskstream_capture_buffer_size() const { return audio_dstream_capture_buffer_size; }
 	framecnt_t audio_diskstream_playback_buffer_size() const { return audio_dstream_playback_buffer_size; }
 	uint32_t midi_diskstream_buffer_size()  const { return midi_dstream_buffer_size; }
diff --git a/libs/ardour/ardour/diskstream.h b/libs/ardour/ardour/diskstream.h
index 975c8d45da..039474b5bd 100644
--- a/libs/ardour/ardour/diskstream.h
+++ b/libs/ardour/ardour/diskstream.h
@@ -175,9 +175,6 @@ class Diskstream : public SessionObject, public PublicDiskstream
 	virtual void reset_write_sources (bool, bool force = false) = 0;
 	virtual void non_realtime_input_change () = 0;
 
-	uint32_t read_data_count() const { return _read_data_count; }
-	uint32_t write_data_count() const { return _write_data_count; }
-
   protected:
 	friend class Auditioner;
 	virtual int  seek (framepos_t which_sample, bool complete_refill = false) = 0;
@@ -290,9 +287,6 @@ class Diskstream : public SessionObject, public PublicDiskstream
 	framepos_t     playback_sample;
 	framecnt_t     playback_distance;
 
-	uint32_t     _read_data_count;
-	uint32_t     _write_data_count;
-
 	bool          in_set_state;
 
 	Glib::Mutex state_lock;
diff --git a/libs/ardour/ardour/midi_source.h b/libs/ardour/ardour/midi_source.h
index 735a38faa5..3564fff4fc 100644
--- a/libs/ardour/ardour/midi_source.h
+++ b/libs/ardour/ardour/midi_source.h
@@ -95,9 +95,6 @@ class MidiSource : virtual public Source, public boost::enable_shared_from_this<
 	std::string captured_for() const               { return _captured_for; }
 	void        set_captured_for (std::string str) { _captured_for = str; }
 
-	uint32_t read_data_count()  const { return _read_data_count; }
-	uint32_t write_data_count() const { return _write_data_count; }
-
 	framepos_t last_write_end() const { return _last_write_end; }
 	void set_last_write_end (framepos_t pos) { _last_write_end = pos; }
 
@@ -155,8 +152,6 @@ class MidiSource : virtual public Source, public boost::enable_shared_from_this<
 					   framecnt_t cnt) = 0;
 
 	std::string      _captured_for;
-	mutable uint32_t _read_data_count;  ///< modified in read()
-	mutable uint32_t _write_data_count; ///< modified in write()
 
 	boost::shared_ptr<MidiModel> _model;
 	bool                         _writing;
diff --git a/libs/ardour/ardour/playlist.h b/libs/ardour/ardour/playlist.h
index 934695633e..9e15b9cf5d 100644
--- a/libs/ardour/ardour/playlist.h
+++ b/libs/ardour/ardour/playlist.h
@@ -201,8 +201,6 @@ public:
 	void raise_region_to_top (boost::shared_ptr<Region>);
 	void lower_region_to_bottom (boost::shared_ptr<Region>);
 
-	uint32_t read_data_count() const { return _read_data_count; }
-
 	/* XXX: use of diskstream here is a little unfortunate */
 	const PBD::ID& get_orig_diskstream_id () const { return _orig_diskstream_id; }
 	void set_orig_diskstream_id (const PBD::ID& did) { _orig_diskstream_id = did; }
@@ -292,7 +290,6 @@ public:
 	bool             in_partition;
 	bool            _frozen;
 	uint32_t         subcnt;
-	uint32_t        _read_data_count;
 	PBD::ID         _orig_diskstream_id;
 	uint64_t         layer_op_counter;
 	framecnt_t       freeze_length;
diff --git a/libs/ardour/ardour/public_diskstream.h b/libs/ardour/ardour/public_diskstream.h
index 8dc720963a..3dadf2e8be 100755
--- a/libs/ardour/ardour/public_diskstream.h
+++ b/libs/ardour/ardour/public_diskstream.h
@@ -43,8 +43,6 @@ public:
 	virtual float capture_buffer_load () const = 0;
 	virtual int do_refill () = 0;
 	virtual int do_flush (RunContext, bool force = false) = 0;
-	virtual uint32_t read_data_count() const = 0;
-	virtual uint32_t write_data_count() const = 0;
 	virtual void set_pending_overwrite (bool) = 0;
 	virtual int seek (framepos_t, bool complete_refill = false) = 0;
 	virtual bool hidden () const = 0;
diff --git a/libs/ardour/ardour/region.h b/libs/ardour/ardour/region.h
index 4b3e4623af..a2cc3f4cf7 100644
--- a/libs/ardour/ardour/region.h
+++ b/libs/ardour/ardour/region.h
@@ -221,8 +221,6 @@ class Region
 
 	int apply (Filter &, Progress* progress = 0);
 
-	virtual uint64_t read_data_count () const { return _read_data_count; }
-
 	boost::shared_ptr<ARDOUR::Playlist> playlist () const { return _playlist.lock(); }
 	virtual void set_playlist (boost::weak_ptr<ARDOUR::Playlist>);
 
@@ -385,7 +383,6 @@ class Region
 	Timecode::BBT_Time      _bbt_time;
 	AnalysisFeatureList     _transients;
 
-	mutable uint64_t        _read_data_count;  ///< modified in read()
 	uint64_t                _last_layer_op;  ///< timestamp
 	SourceList              _sources;
 	/** Used when timefx are applied, so we can always use the original source */
diff --git a/libs/ardour/ardour/track.h b/libs/ardour/ardour/track.h
index 01b084641d..dd8a17f8ce 100644
--- a/libs/ardour/ardour/track.h
+++ b/libs/ardour/ardour/track.h
@@ -120,8 +120,6 @@ class Track : public Route, public PublicDiskstream
 	float capture_buffer_load () const;
 	int do_refill ();
 	int do_flush (RunContext, bool force = false);
-	uint32_t read_data_count() const;
-	uint32_t write_data_count() const;
 	void set_pending_overwrite (bool);
 	int seek (framepos_t, bool complete_refill = false);
 	bool hidden () const;
diff --git a/libs/ardour/audio_diskstream.cc b/libs/ardour/audio_diskstream.cc
index 7b0e466ae0..80b484f926 100644
--- a/libs/ardour/audio_diskstream.cc
+++ b/libs/ardour/audio_diskstream.cc
@@ -940,8 +940,6 @@ AudioDiskstream::read (Sample* buf, Sample* mixdown_buffer, float* gain_buffer,
 			return -1;
 		}
 
-		_read_data_count = _playlist->read_data_count();
-
 		if (reversed) {
 
 			swap_by_ptr (buf, buf + this_read - 1);
@@ -1218,8 +1216,6 @@ AudioDiskstream::do_flush (RunContext /*context*/, bool force_flush)
 	RingBufferNPT<CaptureTransition>::rw_vector transvec;
 	framecnt_t total;
 
-	_write_data_count = 0;
-
 	transvec.buf[0] = 0;
 	transvec.buf[1] = 0;
 	vector.buf[0] = 0;
@@ -1325,8 +1321,6 @@ AudioDiskstream::do_flush (RunContext /*context*/, bool force_flush)
 				return -1;
 			}
 
-			_write_data_count += (*chan)->write_source->write_data_count();
-
 			(*chan)->capture_buf->increment_read_ptr (to_write);
 			(*chan)->curr_capture_cnt += to_write;
 		}
diff --git a/libs/ardour/audio_playlist.cc b/libs/ardour/audio_playlist.cc
index 094191084d..b62aeb3ee7 100644
--- a/libs/ardour/audio_playlist.cc
+++ b/libs/ardour/audio_playlist.cc
@@ -286,9 +286,6 @@ AudioPlaylist::read (Sample *buf, Sample *mixdown_buffer, float *gain_buffer, fr
 	Glib::RecMutex::Lock rm (region_lock);
 
 	framepos_t const end = start + cnt - 1;
-	_read_data_count = 0;
-
-	_read_data_count = 0;
 
 	RegionList* rlist = regions_to_read (start, start+cnt);
 
@@ -346,16 +343,11 @@ AudioPlaylist::read (Sample *buf, Sample *mixdown_buffer, float *gain_buffer, fr
                         DEBUG_TRACE (DEBUG::AudioPlayback, string_compose ("read from region %1\n", ar->name()));
 			assert(ar);
 			ar->read_at (buf, mixdown_buffer, gain_buffer, start, cnt, chan_n);
-			_read_data_count += ar->read_data_count();
 		}
 
 		for (vector<boost::shared_ptr<Crossfade> >::iterator i = x.begin(); i != x.end(); ++i) {
                         DEBUG_TRACE (DEBUG::AudioPlayback, string_compose ("read from xfade between %1 & %2\n", (*i)->out()->name(), (*i)->in()->name()));
 			(*i)->read_at (buf, mixdown_buffer, gain_buffer, start, cnt, chan_n);
-
-			/* don't JACK up _read_data_count, since its the same data as we just
-			   read from the regions, and the OS should handle that for us.
-			*/
 		}
 	}
 
diff --git a/libs/ardour/audioregion.cc b/libs/ardour/audioregion.cc
index 93c229d52f..9b8df441ee 100644
--- a/libs/ardour/audioregion.cc
+++ b/libs/ardour/audioregion.cc
@@ -433,10 +433,6 @@ AudioRegion::_read_at (const SourceList& srcs, framecnt_t limit,
 		mixdown_buffer += buf_offset;
 	}
 
-	if (rops & ReadOpsCount) {
-		_read_data_count = 0;
-	}
-
 	if (chan_n < n_channels()) {
 
 		boost::shared_ptr<AudioSource> src = boost::dynamic_pointer_cast<AudioSource> (srcs[chan_n]);
@@ -444,10 +440,6 @@ AudioRegion::_read_at (const SourceList& srcs, framecnt_t limit,
 			return 0; /* "read nothing" */
 		}
 
-		if (rops & ReadOpsCount) {
-			_read_data_count += src->read_data_count();
-		}
-
 	} else {
 
 		/* track is N-channel, this region has less channels; silence the ones
@@ -465,8 +457,6 @@ AudioRegion::_read_at (const SourceList& srcs, framecnt_t limit,
 				return 0; /* "read nothing" */
 			}
 
-			/* adjust read data count appropriately since this was a duplicate read */
-			src->dec_read_data_count (to_read);
 		} else {
 			memset (mixdown_buffer, 0, sizeof (Sample) * cnt);
 		}
diff --git a/libs/ardour/audiosource.cc b/libs/ardour/audiosource.cc
index 612c4bd73f..e9e7228421 100644
--- a/libs/ardour/audiosource.cc
+++ b/libs/ardour/audiosource.cc
@@ -68,8 +68,6 @@ AudioSource::AudioSource (Session& s, string name)
 	_peaks_built = false;
 	_peak_byte_max = 0;
 	_peakfile_descriptor = 0;
-	_read_data_count = 0;
-	_write_data_count = 0;
 	peak_leftover_cnt = 0;
 	peak_leftover_size = 0;
 	peak_leftovers = 0;
@@ -83,8 +81,6 @@ AudioSource::AudioSource (Session& s, const XMLNode& node)
 	_peaks_built = false;
 	_peak_byte_max = 0;
 	_peakfile_descriptor = 0;
-	_read_data_count = 0;
-	_write_data_count = 0;
 	peak_leftover_cnt = 0;
 	peak_leftover_size = 0;
 	peak_leftovers = 0;
@@ -950,18 +946,6 @@ AudioSource::available_peaks (double zoom_factor) const
 	return (end/sizeof(PeakData)) * _FPP;
 }
 
-void
-AudioSource::dec_read_data_count (framecnt_t cnt)
-{
-        uint32_t val = cnt * sizeof (Sample);
-
-        if (val < _read_data_count) {
-                _read_data_count -= val;
-        } else {
-                _read_data_count = 0;
-        }
-}
-
 void
 AudioSource::mark_streaming_write_completed ()
 {
diff --git a/libs/ardour/butler.cc b/libs/ardour/butler.cc
index 46bb830cbe..7a5d50d06d 100644
--- a/libs/ardour/butler.cc
+++ b/libs/ardour/butler.cc
@@ -35,9 +35,6 @@
 
 using namespace PBD;
 
-static float _read_data_rate;
-static float _write_data_rate;
-
 namespace ARDOUR {
 
 Butler::Butler(Session& s)
@@ -144,9 +141,6 @@ void *
 Butler::thread_work ()
 {
 	uint32_t err = 0;
-	int32_t bytes;
-	bool compute_io;
-	microseconds_t begin, end;
 
 	struct pollfd pfd[1];
 	bool disk_work_outstanding = false;
@@ -217,9 +211,6 @@ Butler::thread_work ()
 		}
 
 
-		bytes = 0;
-		compute_io = true;
-
 restart:
 		disk_work_outstanding = false;
 
@@ -227,8 +218,6 @@ restart:
 			_session.butler_transport_work ();
 		}
 
-		begin = get_microseconds();
-
 		boost::shared_ptr<RouteList> rl = _session.get_routes();
 
 		RouteList rl_with_auditioner = *rl;
@@ -254,16 +243,11 @@ restart:
 			}
 
 			switch (tr->do_refill ()) {
-			case 0:
-				bytes += tr->read_data_count();
-				break;
 			case 1:
-				bytes += tr->read_data_count();
 				disk_work_outstanding = true;
 				break;
 
 			default:
-				compute_io = false;
 				error << string_compose(_("Butler read ahead failure on dstream %1"), (*i)->name()) << endmsg;
 				break;
 			}
@@ -279,19 +263,6 @@ restart:
 			goto restart;
 		}
 
-		if (compute_io) {
-			end = get_microseconds();
-			if (end - begin > 0) {
-				_read_data_rate = (float) bytes / (float) (end - begin);
-			} else {
-				_read_data_rate = 0; // infinity better
-			}
-		}
-
-		bytes = 0;
-		compute_io = true;
-		begin = get_microseconds();
-
 		for (i = rl->begin(); !transport_work_requested() && should_run && i != rl->end(); ++i) {
 			// cerr << "write behind for " << (*i)->name () << endl;
 
@@ -305,17 +276,12 @@ restart:
 			 */
 
 			switch (tr->do_flush (ButlerContext)) {
-			case 0:
-				bytes += tr->write_data_count();
-				break;
 			case 1:
-				bytes += tr->write_data_count();
 				disk_work_outstanding = true;
 				break;
 
 			default:
 				err++;
-				compute_io = false;
 				error << string_compose(_("Butler write-behind failure on dstream %1"), (*i)->name()) << endmsg;
 				/* don't break - try to flush all streams in case they
 				   are split across disks.
@@ -339,16 +305,6 @@ restart:
 			goto restart;
 		}
 
-		if (compute_io) {
-			// there are no apparent users for this calculation?
-			end = get_microseconds();
-			if (end - begin > 0) {
-				_write_data_rate = (float) bytes / (float) (end - begin);
-			} else {
-				_write_data_rate = 0; // Well, infinity would be better
-			}
-		}
-
 		if (!disk_work_outstanding) {
 			_session.refresh_disk_space ();
 		}
@@ -414,24 +370,6 @@ Butler::transport_work_requested () const
 	return g_atomic_int_get(&should_do_transport_work);
 }
 
-float
-Butler::read_data_rate () const
-{
-	/* disk i/o in excess of 10000MB/sec indicate the buffer cache
-	   in action. ignore it.
-	*/
-	return _read_data_rate > 10485.7600000f ? 0.0f : _read_data_rate;
-}
-
-float
-Butler::write_data_rate () const
-{
-	/* disk i/o in excess of 10000MB/sec indicate the buffer cache
-	   in action. ignore it.
-	*/
-	return _write_data_rate > 10485.7600000f ? 0.0f : _write_data_rate;
-}
-
 void
 Butler::empty_pool_trash ()
 {
diff --git a/libs/ardour/coreaudiosource.cc b/libs/ardour/coreaudiosource.cc
index 09e06a49bc..ef99b9afcf 100644
--- a/libs/ardour/coreaudiosource.cc
+++ b/libs/ardour/coreaudiosource.cc
@@ -174,7 +174,6 @@ CoreAudioSource::read_unlocked (Sample *dst, framepos_t start, framecnt_t cnt) c
 
 		if (n_channels == 1) {
 			if (safe_read (dst, start, file_cnt, abl) == 0) {
-				_read_data_count = cnt * sizeof (Sample);
 				return cnt;
 			}
 			return 0;
@@ -187,8 +186,6 @@ CoreAudioSource::read_unlocked (Sample *dst, framepos_t start, framecnt_t cnt) c
 		return 0;
 	}
 
-	_read_data_count = cnt * sizeof(float);
-
 	Sample *ptr = interleave_buf + _channel;
 
 	/* stride through the interleaved data */
diff --git a/libs/ardour/diskstream.cc b/libs/ardour/diskstream.cc
index 21bbbbd849..3c79d31f98 100644
--- a/libs/ardour/diskstream.cc
+++ b/libs/ardour/diskstream.cc
@@ -110,8 +110,6 @@ Diskstream::Diskstream (Session &sess, const string &name, Flag flag)
         , file_frame (0)
         , playback_sample (0)
         , playback_distance (0)
-        , _read_data_count (0)
-        , _write_data_count (0)
         , in_set_state (false)
         , _flags (flag)
         , deprecated_io_node (0)
@@ -153,8 +151,6 @@ Diskstream::Diskstream (Session& sess, const XMLNode& /*node*/)
         , file_frame (0)
         , playback_sample (0)
         , playback_distance (0)
-        , _read_data_count (0)
-        , _write_data_count (0)
         , in_set_state (false)
         , _flags (Recordable)
         , deprecated_io_node (0)
diff --git a/libs/ardour/midi_diskstream.cc b/libs/ardour/midi_diskstream.cc
index f252c8741e..d9e7c54f2d 100644
--- a/libs/ardour/midi_diskstream.cc
+++ b/libs/ardour/midi_diskstream.cc
@@ -769,8 +769,6 @@ MidiDiskstream::read (framepos_t& start, framecnt_t dur, bool reversed)
 
 		g_atomic_int_add(&_frames_written_to_ringbuffer, this_read);
 
-		_read_data_count = _playlist->read_data_count();
-
 		if (reversed) {
 
 			// Swap note ons with note offs here.  etc?
@@ -873,8 +871,6 @@ MidiDiskstream::do_flush (RunContext /*context*/, bool force_flush)
 
 	assert (!destructive());
 
-	_write_data_count = 0;
-
 	total = _session.transport_frame() - _write_source->last_write_end();
 
 	if (total == 0 || 
diff --git a/libs/ardour/midi_playlist.cc b/libs/ardour/midi_playlist.cc
index f2b8722ce3..3486c38754 100644
--- a/libs/ardour/midi_playlist.cc
+++ b/libs/ardour/midi_playlist.cc
@@ -102,8 +102,6 @@ MidiPlaylist::read (Evoral::EventSink<framepos_t>& dst, framepos_t start, framec
 
 	framepos_t end = start + dur - 1;
 
-	_read_data_count = 0;
-
 	// relevent regions overlapping start <--> end
 	vector< boost::shared_ptr<Region> > regs;
 	typedef pair<MidiStateTracker*,framepos_t> TrackerInfo;
@@ -181,8 +179,6 @@ MidiPlaylist::read (Evoral::EventSink<framepos_t>& dst, framepos_t start, framec
 				_note_trackers.insert (newpair);
 				DEBUG_TRACE (DEBUG::MidiPlaylistIO, "\tadded tracker to trackers\n");
 			}
-
-			_read_data_count += mr->read_data_count();
 		}
 
 	} else {
@@ -234,7 +230,6 @@ MidiPlaylist::read (Evoral::EventSink<framepos_t>& dst, framepos_t start, framec
 
 
 			mr->read_at (evlist, start, dur, chan_n, _note_mode, tracker);
-			_read_data_count += mr->read_data_count();
 
 #ifndef NDEBUG
 			DEBUG_TRACE (DEBUG::MidiPlaylistIO, string_compose ("After %1 (%2 .. %3) we now have %4\n", mr->name(), mr->position(), mr->last_frame(), evlist.size()));
diff --git a/libs/ardour/midi_region.cc b/libs/ardour/midi_region.cc
index 124998b5df..f501390c24 100644
--- a/libs/ardour/midi_region.cc
+++ b/libs/ardour/midi_region.cc
@@ -222,8 +222,6 @@ MidiRegion::_read_at (const SourceList& /*srcs*/, Evoral::EventSink<framepos_t>&
 		return 0; /* read nothing */
 	}
 
-	_read_data_count = 0;
-
 	boost::shared_ptr<MidiSource> src = midi_source(chan_n);
 	src->set_note_mode(mode);
 
@@ -248,8 +246,6 @@ MidiRegion::_read_at (const SourceList& /*srcs*/, Evoral::EventSink<framepos_t>&
 		return 0; /* "read nothing" */
 	}
 
-	_read_data_count += src->read_data_count();
-
 	return to_read;
 }
 
diff --git a/libs/ardour/midi_source.cc b/libs/ardour/midi_source.cc
index 1f4525b7b8..1093cb2c4b 100644
--- a/libs/ardour/midi_source.cc
+++ b/libs/ardour/midi_source.cc
@@ -55,8 +55,6 @@ PBD::Signal1<void,MidiSource*> MidiSource::MidiSourceCreated;
 
 MidiSource::MidiSource (Session& s, string name, Source::Flag flags)
 	: Source(s, DataType::MIDI, name, flags)
-	, _read_data_count(0)
-	, _write_data_count(0)
 	, _writing(false)
 	, _model_iter_valid(false)
 	, _length_beats(0.0)
@@ -67,17 +65,12 @@ MidiSource::MidiSource (Session& s, string name, Source::Flag flags)
 
 MidiSource::MidiSource (Session& s, const XMLNode& node)
 	: Source(s, node)
-	, _read_data_count(0)
-	, _write_data_count(0)
 	, _writing(false)
 	, _model_iter_valid(false)
 	, _length_beats(0.0)
 	, _last_read_end(0)
 	, _last_write_end(0)
 {
-	_read_data_count = 0;
-	_write_data_count = 0;
-
 	if (set_state (node, Stateful::loading_state_version)) {
 		throw failed_constructor();
 	}
diff --git a/libs/ardour/playlist.cc b/libs/ardour/playlist.cc
index 0e86d72bb1..3bc5f57577 100644
--- a/libs/ardour/playlist.cc
+++ b/libs/ardour/playlist.cc
@@ -185,7 +185,6 @@ Playlist::Playlist (boost::shared_ptr<const Playlist> other, string namestr, boo
 	in_flush = false;
 	in_partition = false;
 	subcnt = 0;
-	_read_data_count = 0;
 	_frozen = other->_frozen;
 
 	layer_op_counter = other->layer_op_counter;
@@ -319,7 +318,6 @@ Playlist::init (bool hide)
 	in_flush = false;
 	in_partition = false;
 	subcnt = 0;
-	_read_data_count = 0;
 	_frozen = false;
 	layer_op_counter = 0;
 	freeze_length = 0;
diff --git a/libs/ardour/region.cc b/libs/ardour/region.cc
index c0156903b3..dc3f39daee 100644
--- a/libs/ardour/region.cc
+++ b/libs/ardour/region.cc
@@ -217,7 +217,6 @@ Region::Region (Session& s, framepos_t start, framecnt_t length, const string& n
 	, _last_length (length)
 	, _last_position (0)
 	, _first_edit (EditChangesNothing)
-	, _read_data_count(0)
 	, _last_layer_op(0)
 	, _pending_explicit_relayer (false)
 {
@@ -234,7 +233,6 @@ Region::Region (const SourceList& srcs)
 	, _last_length (0)
 	, _last_position (0)
 	, _first_edit (EditChangesNothing)
-	, _read_data_count(0)
 	, _last_layer_op (0)
 	, _pending_explicit_relayer (false)
 {
@@ -256,7 +254,6 @@ Region::Region (boost::shared_ptr<const Region> other)
 	, _last_length (other->_last_length)
 	, _last_position(other->_last_position) \
 	, _first_edit (EditChangesNothing)
-	, _read_data_count(0)
 	, _last_layer_op (0)
 	, _pending_explicit_relayer (false)
 
@@ -329,7 +326,6 @@ Region::Region (boost::shared_ptr<const Region> other, frameoffset_t offset)
 	, _last_length (other->_last_length)
 	, _last_position(other->_last_position) \
 	, _first_edit (EditChangesNothing)
-	, _read_data_count(0)
 	, _last_layer_op (0)
 	, _pending_explicit_relayer (false)
 
@@ -387,7 +383,6 @@ Region::Region (boost::shared_ptr<const Region> other, const SourceList& srcs)
 	, _last_length (other->_last_length)
 	, _last_position (other->_last_position)
 	, _first_edit (EditChangesID)
-	, _read_data_count (0)
 	, _last_layer_op (other->_last_layer_op)
 	, _pending_explicit_relayer (false)
 {
diff --git a/libs/ardour/smf_source.cc b/libs/ardour/smf_source.cc
index 877882abcb..822e518e3f 100644
--- a/libs/ardour/smf_source.cc
+++ b/libs/ardour/smf_source.cc
@@ -127,8 +127,6 @@ SMFSource::read_unlocked (Evoral::EventSink<framepos_t>& destination, framepos_t
 
 	DEBUG_TRACE (DEBUG::MidiSourceIO, string_compose ("SMF read_unlocked: start %1 duration %2\n", start, duration));
 
-	_read_data_count = 0;
-
 	// Output parameters for read_event (which will allocate scratch in buffer as needed)
 	uint32_t ev_delta_t = 0;
 	uint32_t ev_type    = 0;
@@ -203,8 +201,6 @@ SMFSource::read_unlocked (Evoral::EventSink<framepos_t>& destination, framepos_t
 			break;
 		}
 
-		_read_data_count += ev_size;
-
 		if (ev_size > scratch_size) {
 			scratch_size = ev_size;
 		}
@@ -225,8 +221,6 @@ SMFSource::write_unlocked (MidiRingBuffer<framepos_t>& source, framepos_t positi
                 mark_streaming_write_started ();
         }
 
-	_write_data_count = 0;
-
 	framepos_t        time;
 	Evoral::EventType type;
 	uint32_t          size;
@@ -335,9 +329,6 @@ SMFSource::append_event_unlocked_beats (const Evoral::Event<double>& ev)
 
 	Evoral::SMF::append_event_delta(delta_time_ticks, ev.size(), ev.buffer(), event_id);
 	_last_ev_time_beats = ev.time();
-
-	_write_data_count += ev.size();
-
 }
 
 /** Append an event with a timestamp in frames (framepos_t) */
@@ -385,9 +376,6 @@ SMFSource::append_event_unlocked_frames (const Evoral::Event<framepos_t>& ev, fr
 
 	Evoral::SMF::append_event_delta(delta_time_ticks, ev.size(), ev.buffer(), event_id);
 	_last_ev_time_frames = ev.time();
-
-	_write_data_count += ev.size();
-
 }
 
 XMLNode&
diff --git a/libs/ardour/sndfilesource.cc b/libs/ardour/sndfilesource.cc
index 47571cead6..ee4d976f16 100644
--- a/libs/ardour/sndfilesource.cc
+++ b/libs/ardour/sndfilesource.cc
@@ -327,7 +327,6 @@ SndFileSource::read_unlocked (Sample *dst, framepos_t start, framecnt_t cnt) con
 
 		if (_info.channels == 1) {
 			framecnt_t ret = sf_read_float (sf, dst, file_cnt);
-			_read_data_count = ret * sizeof(float);
 			if (ret != file_cnt) {
 				char errbuf[256];
 				sf_error_str (0, errbuf, sizeof (errbuf) - 1);
@@ -353,8 +352,6 @@ SndFileSource::read_unlocked (Sample *dst, framepos_t start, framecnt_t cnt) con
 		ptr += _info.channels;
 	}
 
-	_read_data_count = cnt * sizeof(float);
-
 	_descriptor->release ();
 	return nread;
 }
@@ -401,8 +398,6 @@ SndFileSource::nondestructive_write_unlocked (Sample *data, framecnt_t cnt)
 		compute_and_write_peaks (data, frame_pos, cnt, false, true);
 	}
 
-	_write_data_count = cnt;
-
 	return cnt;
 }
 
diff --git a/libs/ardour/track.cc b/libs/ardour/track.cc
index 734c8f994d..a91d31fe52 100644
--- a/libs/ardour/track.cc
+++ b/libs/ardour/track.cc
@@ -618,12 +618,6 @@ Track::use_new_playlist ()
 	return _diskstream->use_new_playlist ();
 }
 
-uint32_t
-Track::read_data_count () const
-{
-	return _diskstream->read_data_count ();
-}
-
 void
 Track::set_align_style (AlignStyle s, bool force)
 {
@@ -636,12 +630,6 @@ Track::set_align_choice (AlignChoice s, bool force)
 	_diskstream->set_align_choice (s, force);
 }
 
-uint32_t
-Track::write_data_count () const
-{
-	return _diskstream->write_data_count ();
-}
-
 PBD::ID const &
 Track::diskstream_id () const
 {