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The recommended simplest way of running parallel analysis is to use the "MPIDataSource" pattern.  This allows you to write code as if it was running only on one processor and store small per-event information (numbers and small arrays) as well as "end of run" summary data.  This data can optionally be saved to a small HDF5 file, which can be copied, for example, to a laptop computer for analysis with any software that can read that format.  This script can be found in /reg/g/psdm/tutorials/examplePython/mpiDataSource.py

This script can be run in real-time while data is being taken, and will typically complete a few minutes after the run ends.

Code Block
from psana import *

dsource = MPIDataSource('exp=xpptut15:run=54:smd')
cspaddet = Detector('cspad')
smldata = dsource.small_data('run54.h5',gather_interval=100)

partial_run_sum = None
for nevt,evt in enumerate(dsource.events()):
   calib = cspaddet.calib(evt)
   if calib is None: continue
   cspad_sum = calib.sum()      # number
   cspad_roi = calib[0][0][3:5] # array
   if partial_run_sum is None:
      partial_run_sum = cspad_roi
   else:
      partial_run_sum += cspad_roi

   # save per-event data
   smldata.event(cspad_sum=cspad_sum,cspad_roi=cspad_roi)

   if nevt>3: break

# get "summary" data
run_sum = smldata.sum(partial_run_sum)
# save HDF5 file, including summary data
smldata.save(run_sum=run_sum)

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