Losing data

Created by: germasch

I'll put up the testing code as a PR, so you can check yourself. The tests does use multiblock writing to write an 10-element array in two pieces. (It can run in parallel, but the problem happens in serial, too). Using two Mode::Sync Puts:

[kai@macbook build (pr/bug)]$ bin/bpls -dD multi_sync.bp
  double   var   {10}
        step 0:
          block 0: [0:4]
    (0)    0 1 2 3 4
          block 1: [5:9]
    (0)    5 6 7 8 9

Looks good. Using two Mode::Deferred puts, same result. Good.

Now using a deferred put for one block and a sync put for the other:

[kai@macbook build (pr/bug)]$ bin/bpls -dD multi_ds.bp
  double   var   {10}
        step 0:
          block 0: [5:9]
    (0)    5 6 7 8 9

Oops, ADIOS2 lost half of my data.