Bring back down default bars frame count for ib

The most important changes include:
- iterating the new `Flow` type and updating graphics
- adding detailed profiling
- increasing the min uppx before graphics updates are throttled
- including the L1 spread in y-range calcs so that you never have the
  bid/ask go "out of view"..
- pass around `Flow`s instead of shms
- drop all the old prototyped downsampling code

piker/brokers/ib.py

@@ -1592,7 +1592,7 @@ async def backfill_bars(
     # on that until we have the `marketstore` daemon in place in which
     # case the shm size will be driven by user config and available sys
     # memory.
-    count: int = 59,
+    count: int = 22,
 
     task_status: TaskStatus[trio.CancelScope] = trio.TASK_STATUS_IGNORED,
 

piker/data/_sharedmem.py

@@ -240,7 +240,13 @@ class ShmArray:
     def last(
         self,
         length: int = 1,
+
     ) -> np.ndarray:
+        '''
+        Return the last ``length``'s worth of ("row") entries from the
+        array.
+
+        '''
         return self.array[-length:]
 
     def push(

piker/ui/_chart.py

@@ -658,102 +658,6 @@ class LinkedSplits(QWidget):
                 cpw.sidepane.setMaximumWidth(sp_w)
 
 
-# class FlowsTable(pydantic.BaseModel):
-#     '''
-#     Data-AGGRegate: high level API onto multiple (categorized)
-#     ``Flow``s with high level processing routines for
-#     multi-graphics computations and display.
-
-#     '''
-#     flows: dict[str, np.ndarray] = {}
-
-
-class Flow(msgspec.Struct):  # , frozen=True):
-    '''
-    (FinancialSignal-)Flow compound type which wraps a real-time
-    graphics (curve) and its backing data stream together for high level
-    access and control.
-
-    The intention is for this type to eventually be capable of shm-passing
-    of incrementally updated graphics stream data between actors.
-
-    '''
-    name: str
-    plot: pg.PlotItem
-    is_ohlc: bool = False
-
-    # TODO: hackery to be able to set a shm later
-    # but whilst also allowing this type to hashable,
-    # likely will require serializable token that is used to attach
-    # to the underlying shm ref after startup?
-    _shm: Optional[ShmArray] = None  # currently, may be filled in "later"
-
-    # cache of y-range values per x-range input.
-    _mxmns: dict[tuple[int, int], tuple[float, float]] = {}
-
-    @property
-    def shm(self) -> ShmArray:
-        return self._shm
-
-    @shm.setter
-    def shm(self, shm: ShmArray) -> ShmArray:
-        self._shm = shm
-
-    def maxmin(
-        self,
-        lbar,
-        rbar,
-
-    ) -> tuple[float, float]:
-        '''
-        Compute the cached max and min y-range values for a given
-        x-range determined by ``lbar`` and ``rbar``.
-
-        '''
-        rkey = (lbar, rbar)
-        result = self._mxmns.get(rkey)
-        if result:
-            return result
-
-        shm = self.shm
-        if shm is None:
-            # print(f'no shm {self.name}?')
-            return 0, 0
-
-        arr = shm.array
-
-        # build relative indexes into shm array
-        # TODO: should we just add/use a method
-        # on the shm to do this?
-        ifirst = arr[0]['index']
-        slice_view = arr[
-            lbar - ifirst:(rbar - ifirst) + 1]
-
-        if not slice_view.size:
-            # print(f'no data in view {self.name}?')
-            return 0, 0
-
-        if self.is_ohlc:
-            ylow = np.min(slice_view['low'])
-            yhigh = np.max(slice_view['high'])
-
-        else:
-            view = slice_view[self.name]
-            ylow = np.min(view)
-            yhigh = np.max(view)
-        # else:
-        #     ylow, yhigh = 0, 0
-
-        result = ylow, yhigh
-
-        if result != (0, 0):
-            self._mxmns[rkey] = result
-
-        if self.name == 'drk_vlm':
-            print(f'{self.name} mxmn @ {rkey} -> {result}')
-        return result
-
-
 class ChartPlotWidget(pg.PlotWidget):
     '''
     ``GraphicsView`` subtype containing a single ``PlotItem``.
@@ -1086,6 +990,7 @@ class ChartPlotWidget(pg.PlotWidget):
             name=name,
             plot=self.plotItem,
             is_ohlc=True,
+            graphics=graphics,
         )
 
         self._add_sticky(name, bg_color='davies')
@@ -1159,6 +1064,7 @@ class ChartPlotWidget(pg.PlotWidget):
         overlay: bool = False,
         color: Optional[str] = None,
         add_label: bool = True,
+        pi: Optional[pg.PlotItem] = None,
 
         **pdi_kwargs,
 
@@ -1203,12 +1109,13 @@ class ChartPlotWidget(pg.PlotWidget):
         self._graphics[name] = curve
         self._arrays[data_key] = data
 
-        pi = self.plotItem
+        pi = pi or self.plotItem
 
         self._flows[data_key] = Flow(
             name=name,
             plot=pi,
             is_ohlc=False,
+            graphics=curve,
         )
 
         # TODO: this probably needs its own method?
@@ -1428,6 +1335,7 @@ class ChartPlotWidget(pg.PlotWidget):
 
         '''
         profiler = pg.debug.Profiler(
+            msg=f'`{str(self)}.maxmin()` loop cycle for: `{self.name}`',
             disabled=not pg_profile_enabled(),
             gt=ms_slower_then,
             delayed=True,
@@ -1444,16 +1352,113 @@ class ChartPlotWidget(pg.PlotWidget):
         if (
             flow is None
         ):
-            print(f"flow {flow_key} doesn't exist in chart {self.name}")
+            log.error(f"flow {flow_key} doesn't exist in chart {self.name} !?")
-            return 0, 0
+            res = 0, 0
 
         else:
             key = round(lbar), round(rbar)
             res = flow.maxmin(*key)
-            profiler(f'{key} max-min {res}')
+            profiler(f'yrange mxmn: {key} -> {res}')
-            if res == (0, 0):
+            if res == (None, None):
                 log.error(
-                    f"{flow_key} -> (0, 0) for bars_range = {key}"
+                    f"{flow_key} no mxmn for bars_range => {key} !?"
                 )
+                res = 0, 0
 
         return res
+
+
+# class FlowsTable(pydantic.BaseModel):
+#     '''
+#     Data-AGGRegate: high level API onto multiple (categorized)
+#     ``Flow``s with high level processing routines for
+#     multi-graphics computations and display.
+
+#     '''
+#     flows: dict[str, np.ndarray] = {}
+
+
+class Flow(msgspec.Struct):  # , frozen=True):
+    '''
+    (FinancialSignal-)Flow compound type which wraps a real-time
+    graphics (curve) and its backing data stream together for high level
+    access and control.
+
+    The intention is for this type to eventually be capable of shm-passing
+    of incrementally updated graphics stream data between actors.
+
+    '''
+    name: str
+    plot: pg.PlotItem
+    is_ohlc: bool = False
+    graphics: pg.GraphicsObject
+
+    # TODO: hackery to be able to set a shm later
+    # but whilst also allowing this type to hashable,
+    # likely will require serializable token that is used to attach
+    # to the underlying shm ref after startup?
+    _shm: Optional[ShmArray] = None  # currently, may be filled in "later"
+
+    # cache of y-range values per x-range input.
+    _mxmns: dict[tuple[int, int], tuple[float, float]] = {}
+
+    @property
+    def shm(self) -> ShmArray:
+        return self._shm
+
+    @shm.setter
+    def shm(self, shm: ShmArray) -> ShmArray:
+        self._shm = shm
+
+    def maxmin(
+        self,
+        lbar,
+        rbar,
+
+    ) -> tuple[float, float]:
+        '''
+        Compute the cached max and min y-range values for a given
+        x-range determined by ``lbar`` and ``rbar``.
+
+        '''
+        rkey = (lbar, rbar)
+        cached_result = self._mxmns.get(rkey)
+        if cached_result:
+            return cached_result
+
+        shm = self.shm
+        if shm is None:
+            mxmn = None
+
+        else:  # new block for profiling?..
+            arr = shm.array
+
+            # build relative indexes into shm array
+            # TODO: should we just add/use a method
+            # on the shm to do this?
+            ifirst = arr[0]['index']
+            slice_view = arr[
+                lbar - ifirst:
+                (rbar - ifirst) + 1
+            ]
+
+            if not slice_view.size:
+                mxmn = None
+
+            else:
+                if self.is_ohlc:
+                    ylow = np.min(slice_view['low'])
+                    yhigh = np.max(slice_view['high'])
+
+                else:
+                    view = slice_view[self.name]
+                    ylow = np.min(view)
+                    yhigh = np.max(view)
+
+                mxmn = ylow, yhigh
+
+            if mxmn is not None:
+                # cache new mxmn result
+                self._mxmns[rkey] = mxmn
+
+            return mxmn

piker/ui/_compression.py

@@ -260,12 +260,13 @@ def ds_m4(
     if log_scale:
         assert uppx, 'You must provide a `uppx` value to use log scaling!'
 
+        # scaler = 2**7 / (1 + math.log(uppx, 2))
         scaler = round(
             max(
                 # NOTE: found that a 16x px width brought greater
                 # detail, likely due to dpi scaling?
                 # px_width=px_width * 16,
-                2**6 / (1 + math.log(uppx, 2)),
+                2**7 / (1 + math.log(uppx, 2)),
                 1
             )
         )

piker/ui/_curve.py

@@ -408,7 +408,7 @@ class FastAppendCurve(pg.GraphicsObject):
 
                 self._in_ds = False
 
-            elif should_ds:
+            elif should_ds and px_width:
                 x_out, y_out = self.downsample(
                     x_out,
                     y_out,

piker/ui/_display.py

@@ -30,7 +30,6 @@ import numpy as np
 import tractor
 import trio
 import pyqtgraph as pg
-from PyQt5.QtCore import QLineF
 
 from .. import brokers
 from ..data.feed import open_feed
@@ -73,13 +72,20 @@ _tick_groups = {
 }
 
 
+# TODO: delegate this to each `Flow.maxmin()` which includes
+# caching and further we should implement the following stream based
+# approach, likely with ``numba``:
+# https://arxiv.org/abs/cs/0610046
+# https://github.com/lemire/pythonmaxmin
 def chart_maxmin(
     chart: ChartPlotWidget,
     ohlcv_shm: ShmArray,
     vlm_chart: Optional[ChartPlotWidget] = None,
 
 ) -> tuple[
+
     tuple[int, int, int, int],
+
     float,
     float,
     float,
@@ -88,11 +94,6 @@ def chart_maxmin(
     Compute max and min datums "in view" for range limits.
 
     '''
-    # TODO: implement this
-    # https://arxiv.org/abs/cs/0610046
-    # https://github.com/lemire/pythonmaxmin
-
-    # array = chart._arrays[chart.name]
     array = ohlcv_shm.array
     ifirst = array[0]['index']
 
@@ -105,18 +106,23 @@ def chart_maxmin(
         chart.default_view()
         return (last_bars_range, 0, 0, 0)
 
-    mx, mn = np.nanmax(in_view['high']), np.nanmin(in_view['low'])
+    mx, mn = (
-
+        np.nanmax(in_view['high']),
-    # TODO: when we start using line charts, probably want to make
+        np.nanmin(in_view['low'],)
-    # this an overloaded call on our `DataView
+    )
-    # sym = chart.name
-    # mx, mn = np.nanmax(in_view[sym]), np.nanmin(in_view[sym])
 
     mx_vlm_in_view = 0
     if vlm_chart:
-        mx_vlm_in_view = np.max(in_view['volume'])
+        mx_vlm_in_view = np.max(
+            in_view['volume']
+        )
 
-    return last_bars_range, mx, max(mn, 0), mx_vlm_in_view
+    return (
+        last_bars_range,
+        mx,
+        max(mn, 0),  # presuming price can't be negative?
+        mx_vlm_in_view,
+    )
 
 
 @dataclass
@@ -272,8 +278,9 @@ async def graphics_update_loop(
 
     chart.default_view()
 
-    # main loop
+    # main real-time quotes update loop
     async for quotes in stream:
+
         ds.quotes = quotes
         quote_period = time.time() - last_quote
         quote_rate = round(
@@ -310,28 +317,50 @@ def graphics_update_cycle(
     wap_in_history: bool = False,
 
 ) -> None:
-
     # TODO: eventually optimize this whole graphics stack with ``numba``
     # hopefully XD
 
+    chart = ds.chart
+
     profiler = pg.debug.Profiler(
+        msg=f'Graphics loop cycle for: `{chart.name}`',
         disabled=True,  # not pg_profile_enabled(),
         gt=1/12 * 1e3,
+        # gt=ms_slower_then,
     )
 
     # unpack multi-referenced components
-    chart = ds.chart
     vlm_chart = ds.vlm_chart
     l1 = ds.l1
-
     ohlcv = ds.ohlcv
     array = ohlcv.array
     vars = ds.vars
     tick_margin = vars['tick_margin']
 
-    update_uppx = 5
+    update_uppx = 6
 
     for sym, quote in ds.quotes.items():
+
+        # compute the first available graphic's x-units-per-pixel
+        xpx = vlm_chart.view.x_uppx()
+
+        # NOTE: vlm may be written by the ``brokerd`` backend
+        # event though a tick sample is not emitted.
+        # TODO: show dark trades differently
+        # https://github.com/pikers/piker/issues/116
+
+        # NOTE: this used to be implemented in a dedicated
+        # "increment task": ``check_for_new_bars()`` but it doesn't
+        # make sense to do a whole task switch when we can just do
+        # this simple index-diff and all the fsp sub-curve graphics
+        # are diffed on each draw cycle anyway; so updates to the
+        # "curve" length is already automatic.
+
+        # increment the view position by the sample offset.
+        i_step = ohlcv.index
+        i_diff = i_step - vars['i_last']
+        vars['i_last'] = i_step
+
         (
             brange,
             mx_in_view,
@@ -344,83 +373,12 @@ def graphics_update_cycle(
         mn = mn_in_view - tick_margin
         profiler('maxmin call')
 
-        # compute the first available graphic's x-units-per-pixel
-        xpx = vlm_chart.view.xs_in_px()
-        # print(f'vlm xpx {xpx}')
-
-        in_view = chart.in_view(ohlcv.array)
-
-        if lbar != rbar:
-            # view box width in pxs
-            w = chart.view.boundingRect().width()
-
-            # TODO: a better way to get this?
-            # i would guess the esiest way is to just
-            # get the ``.boundingRect()`` of the curve
-            # in view but maybe there's something smarter?
-            # Currently we're just mapping the rbar, lbar to
-            # pixels via:
-            cw = chart.view.mapViewToDevice(QLineF(lbar, 0, rbar, 0)).length()
-            # is this faster?
-            # cw = chart.mapFromView(QLineF(lbar, 0 , rbar, 0)).length()
-
-            profiler(
-                f'view width pxs: {w}\n'
-                f'curve width pxs: {cw}\n'
-                f'sliced in view: {in_view.size}'
-            )
-
-            # compress bars to m4 line(s) if uppx is high enough
-            # if in_view.size > cw:
-            #     from ._compression import ds_m4, hl2mxmn
-
-            #     mxmn, x = hl2mxmn(in_view)
-            #     profiler('hl tracer')
-
-            #     nb, x, y = ds_m4(
-            #         x=x,
-            #         y=mxmn,
-            #         # TODO: this needs to actually be the width
-            #         # in pixels of the visible curve since we don't
-            #         # want to downsample any 'zeros' around the curve,
-            #         # just the values that make up the curve graphic,
-            #         # i think?
-            #         px_width=cw,
-            #     )
-            #     profiler(
-            #         'm4 downsampled\n'
-            #         f' ds bins: {nb}\n'
-            #         f' x.shape: {x.shape}\n'
-            #         f' y.shape: {y.shape}\n'
-            #         f' x: {x}\n'
-            #         f' y: {y}\n'
-            #     )
-
-        # assert y.size == mxmn.size
-
-        # NOTE: vlm may be written by the ``brokerd`` backend
-        # event though a tick sample is not emitted.
-        # TODO: show dark trades differently
-        # https://github.com/pikers/piker/issues/116
-
-        # NOTE: this used to be implemented in a dedicated
-        # "increment tas": ``check_for_new_bars()`` but it doesn't
-        # make sense to do a whole task switch when we can just do
-        # this simple index-diff and all the fsp sub-curve graphics
-        # are diffed on each draw cycle anyway; so updates to the
-        # "curve" length is already automatic.
-
-        # increment the view position by the sample offset.
-        i_step = ohlcv.index
-        i_diff = i_step - vars['i_last']
-        vars['i_last'] = i_step
-
         # don't real-time "shift" the curve to the
         # left under the following conditions:
         if (
             i_diff > 0  # no new sample step
             and xpx < update_uppx  # chart is zoomed out very far
-            and r >= i_step  # the last datum isn't in view
+            and r >= i_step  # the last datum is in view
         ):
             # TODO: we should track and compute whether the last
             # pixel in a curve should show new data based on uppx
@@ -429,7 +387,9 @@ def graphics_update_cycle(
 
         if vlm_chart:
             # always update y-label
-            ds.vlm_sticky.update_from_data(*array[-1][['index', 'volume']])
+            ds.vlm_sticky.update_from_data(
+                *array[-1][['index', 'volume']]
+            )
 
             if (
                 # if zoomed out alot don't update the last "bar"
@@ -460,17 +420,17 @@ def graphics_update_cycle(
                     mx_vlm_in_view != last_mx_vlm
                     or mx_vlm_in_view > last_mx_vlm
                 ):
-                    # print(f'mx vlm: {last_mx_vlm} -> {mx_vlm_in_view}')
                     yrange = (0, mx_vlm_in_view * 1.375)
                     vlm_chart.view._set_yrange(
                         yrange=yrange,
                     )
+                    # print(f'mx vlm: {last_mx_vlm} -> {mx_vlm_in_view}')
                     vars['last_mx_vlm'] = mx_vlm_in_view
 
                 for curve_name, flow in vlm_chart._flows.items():
                     update_fsp_chart(
                         vlm_chart,
-                        flow.shm,
+                        flow,
                         curve_name,
                         array_key=curve_name,
                     )
@@ -525,7 +485,6 @@ def graphics_update_cycle(
         # current) tick first order as an optimization where we only
         # update from the last tick from each type class.
         # last_clear_updated: bool = False
-        # for typ, tick in reversed(lasts.items()):
 
         # update ohlc sampled price bars
         if (
@@ -537,7 +496,7 @@ def graphics_update_cycle(
                 array,
             )
 
-        # iterate in FIFO order per frame
+        # iterate in FIFO order per tick-frame
         for typ, tick in lasts.items():
 
             price = tick.get('price')
@@ -608,42 +567,34 @@ def graphics_update_cycle(
         if (
             (mx > vars['last_mx']) or (mn < vars['last_mn'])
             and not chart._static_yrange == 'axis'
+            and r > i_step  # the last datum is in view
         ):
-            # print(f'new y range: {(mn, mx)}')
+            main_vb = chart.view
-            chart.view._set_yrange(
+            if (
-                yrange=(mn, mx),
+                main_vb._ic is None
-                # TODO: we should probably scale
+                or not main_vb._ic.is_set()
-                # the view margin based on the size
+            ):
-                # of the true range? This way you can
+                main_vb._set_yrange(
-                # slap in orders outside the current
+                    # TODO: we should probably scale
-                # L1 (only) book range.
+                    # the view margin based on the size
-                # range_margin=0.1,
+                    # of the true range? This way you can
-            )
+                    # slap in orders outside the current
+                    # L1 (only) book range.
+                    # range_margin=0.1,
+                    yrange=(mn, mx),
+                )
 
         vars['last_mx'], vars['last_mn'] = mx, mn
 
-        # run synchronous update on all derived fsp subplots
+        # run synchronous update on all linked flows
-        for name, subchart in ds.linked.subplots.items():
+        for curve_name, flow in chart._flows.items():
-            if name == 'volume':
+            # TODO: should the "main" (aka source) flow be special?
+            if curve_name == chart.data_key:
                 continue
 
-            update_fsp_chart(
-                subchart,
-                subchart._shm,
-
-                # XXX: do we really needs seperate names here?
-                name,
-                array_key=name,
-            )
-            subchart.cv._set_yrange()
-
-            # TODO: all overlays on all subplots..
-
-        # run synchronous update on all derived overlays
-        for curve_name, flow in chart._flows.items():
             update_fsp_chart(
                 chart,
-                flow.shm,
+                flow,
                 curve_name,
                 array_key=curve_name,
             )
@@ -737,6 +688,7 @@ async def display_symbol_data(
 
         # TODO: a data view api that makes this less shit
         chart._shm = ohlcv
+        chart._flows[chart.data_key].shm = ohlcv
 
         # NOTE: we must immediately tell Qt to show the OHLC chart
         # to avoid a race where the subplots get added/shown to
@@ -793,7 +745,7 @@ async def display_symbol_data(
                 # that it isn't double rendered in the display loop
                 # above since we do a maxmin calc on the volume data to
                 # determine if auto-range adjustements should be made.
-                linked.subplots.pop('volume', None)
+                # linked.subplots.pop('volume', None)
 
                 # TODO: make this not so shit XD
                 # close group status

piker/ui/_fsp.py

@@ -72,12 +72,16 @@ def has_vlm(ohlcv: ShmArray) -> bool:
 
 def update_fsp_chart(
     chart: ChartPlotWidget,
-    shm: ShmArray,
+    flow,
     graphics_name: str,
     array_key: Optional[str],
 
 ) -> None:
 
+    shm = flow.shm
+    if not shm:
+        return
+
     array = shm.array
     last_row = try_read(array)
 
@@ -271,6 +275,7 @@ async def run_fsp_ui(
             # data looked up from the chart's internal array set.
             # TODO: we must get a data view api going STAT!!
             chart._shm = shm
+            chart._flows[chart.data_key].shm = shm
 
             # should **not** be the same sub-chart widget
             assert chart.name != linkedsplits.chart.name
@@ -282,7 +287,7 @@ async def run_fsp_ui(
         # first UI update, usually from shm pushed history
         update_fsp_chart(
             chart,
-            shm,
+            chart._flows[array_key],
             name,
             array_key=array_key,
         )
@@ -441,8 +446,11 @@ class FspAdmin:
             async with stream.subscribe() as stream:
                 async for msg in stream:
                     if msg == 'update':
-                        log.info(f'Re-syncing graphics for fsp: {ns_path}')
+                        # if the chart isn't hidden try to update
-                        self.linked.graphics_cycle()
+                        # the data on screen.
+                        if not self.linked.isHidden():
+                            log.info(f'Re-syncing graphics for fsp: {ns_path}')
+                            self.linked.graphics_cycle()
                     else:
                         log.info(f'recved unexpected fsp engine msg: {msg}')
 
@@ -631,6 +639,7 @@ async def open_vlm_displays(
             # the curve item internals are pretty convoluted.
             style='step',
         )
+        chart._flows['volume'].shm = ohlcv
 
         # force 0 to always be in view
         def maxmin(
@@ -794,13 +803,16 @@ async def open_vlm_displays(
                         color=color,
                         step_mode=step_mode,
                         style=style,
+                        pi=pi,
                     )
 
                     # TODO: we need a better API to do this..
                     # specially store ref to shm for lookup in display loop
                     # since only a placeholder of `None` is entered in
                     # ``.draw_curve()``.
-                    chart._flows[name].shm = shm
+                    flow = chart._flows[name]
+                    assert flow.plot is pi
+                    flow.shm = shm
 
             chart_curves(
                 fields,
@@ -835,6 +847,9 @@ async def open_vlm_displays(
             # liquidity events (well at least on low OHLC periods - 1s).
             vlm_curve.hide()
             chart.removeItem(vlm_curve)
+            chart._flows.pop('volume')
+            # avoid range sorting on volume once disabled
+            chart.view.disable_auto_yrange()
 
             # Trade rate overlay
             # XXX: requires an additional overlay for
@@ -875,7 +890,10 @@ async def open_vlm_displays(
                 style='dash',
             )
 
-            for pi in (dvlm_pi, tr_pi):
+            for pi in (
+                dvlm_pi,
+                tr_pi,
+            ):
                 for name, axis_info in pi.axes.items():
                     # lol this sux XD
                     axis = axis_info['item']

piker/ui/_interaction.py

@@ -393,6 +393,11 @@ class ChartView(ViewBox):
     def start_ic(
         self,
     ) -> None:
+        '''
+        Signal the beginning of a click-drag interaction
+        to any interested task waiters.
+
+        '''
         if self._ic is None:
             self.chart.pause_all_feeds()
             self._ic = trio.Event()
@@ -400,13 +405,13 @@ class ChartView(ViewBox):
     def signal_ic(
         self,
         *args,
-        # ev = None,
-    ) -> None:
-        if args:
-            print(f'range change dun: {args}')
-        else:
-            print('proxy called')
 
+    ) -> None:
+        '''
+        Signal the end of a click-drag interaction
+        to any waiters.
+
+        '''
         if self._ic:
             self._ic.set()
             self._ic = None
@@ -674,7 +679,6 @@ class ChartView(ViewBox):
                 self.sigRangeChangedManually.emit(self.state['mouseEnabled'])
 
                 if ev.isFinish():
-                    print('DRAG FINISH')
                     self.signal_ic()
                     # self._ic.set()
                     # self._ic = None
@@ -780,27 +784,32 @@ class ChartView(ViewBox):
             # TODO: maybe should be a method on the
             # chart widget/item?
             # if False:
-            if autoscale_linked_plots:
+            # if autoscale_linked_plots:
-                # avoid recursion by sibling plots
+            #     # avoid recursion by sibling plots
-                linked = self.linkedsplits
+            #     linked = self.linkedsplits
-                plots = list(linked.subplots.copy().values())
+            #     plots = list(linked.subplots.copy().values())
-                main = linked.chart
+            #     main = linked.chart
-                if main:
+            #     if main:
-                    plots.append(main)
+            #         plots.append(main)
 
-                for chart in plots:
+            #     for chart in plots:
-                    if chart and not chart._static_yrange:
+            #         if chart and not chart._static_yrange:
-                        chart.cv._set_yrange(
+            #             chart.cv._set_yrange(
-                            bars_range=br,
+            #                 bars_range=br,
-                            autoscale_linked_plots=False,
+            #                 autoscale_linked_plots=False,
-                        )
+            #             )
-                profiler('autoscaled linked plots')
+            #     profiler('autoscaled linked plots')
 
         if set_range:
 
-            yrange = self._maxmin()
+            if not yrange:
-            if yrange is None:
+                # XXX: only compute the mxmn range
-                return
+                # if none is provided as input!
+                yrange = self._maxmin()
+
+                if yrange is None:
+                    log.warning(f'No yrange provided for {self.name}!?')
+                    return
 
             ylow, yhigh = yrange
 
@@ -834,8 +843,17 @@ class ChartView(ViewBox):
         if src_vb is None:
             src_vb = self
 
+        # such that when a linked chart changes its range
+        # this local view is also automatically changed and
+        # resized to data.
         src_vb.sigXRangeChanged.connect(self._set_yrange)
 
+        # splitter(s) resizing
+        src_vb.sigResized.connect(self._set_yrange)
+
+        # mouse wheel doesn't emit XRangeChanged
+        src_vb.sigRangeChangedManually.connect(self._set_yrange)
+
         # TODO: a smarter way to avoid calling this needlessly?
         # 2 things i can think of:
         # - register downsample-able graphics specially and only
@@ -846,17 +864,24 @@ class ChartView(ViewBox):
             self.maybe_downsample_graphics
         )
 
-        # mouse wheel doesn't emit XRangeChanged
-        src_vb.sigRangeChangedManually.connect(self._set_yrange)
-
-        # splitter(s) resizing
-        src_vb.sigResized.connect(self._set_yrange)
-
     def disable_auto_yrange(
         self,
     ) -> None:
 
-        self._chart._static_yrange = 'axis'
+        # self._chart._static_yrange = 'axis'
+
+        self.sigXRangeChanged.disconnect(
+            self._set_yrange,
+        )
+        self.sigResized.disconnect(
+            self._set_yrange,
+        )
+        self.sigRangeChangedManually.disconnect(
+            self.maybe_downsample_graphics
+        )
+        self.sigRangeChangedManually.disconnect(
+            self._set_yrange,
+        )
 
     def x_uppx(self) -> float:
         '''
@@ -902,8 +927,8 @@ class ChartView(ViewBox):
         linked = self.linkedsplits
         plots = linked.subplots | {chart.name: chart}
         for chart_name, chart in plots.items():
-            for name, graphics in chart._graphics.items():
+            for name, flow in chart._flows.items():
-                # print(f'maybe ds chart:{name} graphic:{name}')
+                graphics = flow.graphics
 
                 use_vr = False
                 if isinstance(graphics, BarItems):