Incomplete merge of event-data in MPI mode may cause an incomplete mccode.sim

[willend]

Seen on Windows in a (big) MPI-run with 72 cores.

After the end of simulation, dataset was not plot-able, mcplot output:

/Applications/McStas-3.1.app/Contents/Resources/mcstas/3.1/tools/Python/mcplot/pyqtgraph/plotfuncs.py:183: VisibleDeprecationWarning: Creating an ndarray from ragged nested sequences (which is a list-or-tuple of lists-or-tuples-or ndarrays with different lengths or shapes) is deprecated. If you meant to do this, you must specify 'dtype=object' when creating the ndarray.
  dataset = np.array(data.zvals)
mcplot error: tuple index out of range
Traceback (most recent call last):
  File "/Applications/McStas-3.1.app/Contents/Resources/mcstas/3.1/bin/../tools/Python/mcplot/pyqtgraph/mcplot.py", line 67, in <module>
    main(args)
  File "/Applications/McStas-3.1.app/Contents/Resources/mcstas/3.1/bin/../tools/Python/mcplot/pyqtgraph/mcplot.py", line 57, in main
    raise e
  File "/Applications/McStas-3.1.app/Contents/Resources/mcstas/3.1/bin/../tools/Python/mcplot/pyqtgraph/mcplot.py", line 51, in main
    plotter.runplot()
  File "/Applications/McStas-3.1.app/Contents/Resources/mcstas/3.1/tools/Python/mcplot/pyqtgraph/../../mccodelib/pqtgfrontend.py", line 62, in runplot
    plot_node(node, self.plot_func, plt_layout, viewmodel)
  File "/Applications/McStas-3.1.app/Contents/Resources/mcstas/3.1/tools/Python/mcplot/pyqtgraph/../../mccodelib/pqtgfrontend.py", line 144, in plot_node
    viewbox_lst.append(add_plot(layout, node, plot_func, i, n, viewmodel))
  File "/Applications/McStas-3.1.app/Contents/Resources/mcstas/3.1/tools/Python/mcplot/pyqtgraph/../../mccodelib/pqtgfrontend.py", line 382, in add_plot
    view_box, plt_itm = plot_node_func(node, i, plt, options)
  File "/Applications/McStas-3.1.app/Contents/Resources/mcstas/3.1/tools/Python/mcplot/pyqtgraph/plotfuncs.py", line 33, in plot
    view_box, lyt = plot_Data2D(data, plt, log=opts['log'], legend=opts['legend'], icolormap=opts['icolormap'],
  File "/Applications/McStas-3.1.app/Contents/Resources/mcstas/3.1/tools/Python/mcplot/pyqtgraph/plotfuncs.py", line 198, in plot_Data2D
    img.setImage(dataset)
  File "/opt/homebrew/lib/python3.9/site-packages/pyqtgraph/graphicsItems/ImageItem.py", line 286, in setImage
    if self.image.shape[0] > 2**15-1 or self.image.shape[1] > 2**15-1:
IndexError: tuple index out of range

Investigation shows that the mccode.sim is truncated, ends like this:

begin data
 Date: Mon Aug 08 10:54:02 2022 (1659948842)
 type: array_2d(6, 5)
 Source: EGCESE (BifrostFullSpectrometer.instr)
 component: event_1
 position: 1.52851 -1.55771 163.591
 title:  Intensity Position Position Energy Time_Of_Flight tof at sample Monitor (Square)
 Ncount: 999936
 filename: event_1_dat_list.p.x.y.E.t.U1
 statistics: X0=0; dX=0; Y0=0; dY=0;
 signal: Min=0.322215; Max=0.322215; Mean=0;
 values: 0 0 0
 xvar: List
 yvar: p
 xlabel: List of neutron events
 ylabel: p x y E t U1 
 zvar: I
 zlabel: Signal per bin
 xylimits: 1 5 1 6
 variables: p x y E t U1 

It is uncertain wether the simulation ended up with a complete dataset later.

• We should consider to avoid monitor entries for event lists alltogether.

[willend]

BifrostFullSpectrometer_20220808_105354.zip

[willend]

Related? It looks like the Python interpreter may have been overwhelmed by lots of text output from the many MPI cores...

[willend]

(Here from 32 processes on DTU windows box)