[Paraview] Problem about pvts data

[Nancy]

Hi, all,

I have created a data with .pvts format, like following:
<?xml version="1.0"?>
<VTKFile type="PStructuredGrid" version="0.1" byte_order="LittleEndian" compressor="vtkZLibDataCompressor">
 <PStructuredGrid WholeExtent="0 100 0 100 0 100" GhostLevel="0">
  <PPointData>
  <PDataArray type="Float32" Name="energy"/>
  <PDataArray type="Float32" Name="Dens1"/>
  <PDataArray type="Float32" Name="Dens0"/>
 </PPointData>
  <PPoints>
   <PDataArray type="Float32" NumberOfComponents="3"/>
  </PPoints>
 <Piece Extent="0 50 0 50 0 50" Source="field-0-1.000.vts"/>
 <Piece Extent="0 50 0 50 50 100" Source="field-1-1.000.vts"/>
 <Piece Extent="0 50 50 100 0 50" Source="field-2-1.000.vts"/>
 <Piece Extent="0 50 50 100 50 100" Source="field-3-1.000.vts"/>
 <Piece Extent="50 100 0 50 0 50" Source="field-4-1.000.vts"/>
 <Piece Extent="50 100 0 50 50 100" Source="field-5-1.000.vts"/>
 <Piece Extent="50 100 50 100 0 50" Source="field-6-1.000.vts"/>
 <Piece Extent="50 100 50 100 50 100" Source="field-7-1.000.vts"/>
</PStructuredGrid>
</VTKFile>

But, when I start paraview in c/s parallel mode with 4 nodes as servers (mpirun -np 4 pvserver),
and load above .pvts data, only the first 4 pieces are showed on screen. If I use 2 nodes as servers,
also only the first 2 pieces are loaded. 
Why? Any help is welcome.
Thank you!

------------------				 
Nancy
2006-07-21