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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Jie<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoListParagraph" style="text-indent:-18.0pt;mso-list:l0 level1 lfo1"><![if !supportLists]><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><span style="mso-list:Ignore">1)<span style="font:7.0pt "Times New Roman"">
</span></span></span><![endif]><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">each reader/source must split pieces itself. If I am a vtkSTUFFreader, when I execute, I am given a piece number or an extent (depending on datatype),
based on this information, I read the part of the data that I was told to (the reader has to work out how to get the piece it was asked for)<o:p></o:p></span></p>
<p class="MsoListParagraph" style="text-indent:-18.0pt;mso-list:l0 level1 lfo1"><![if !supportLists]><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><span style="mso-list:Ignore">2)<span style="font:7.0pt "Times New Roman"">
</span></span></span><![endif]><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">The number of pieces is currently always the same as the number of MPI ranks (but it doesn’t have to be). A reader can set MAX_PIECES to -1 initially
before the description in 1) above happens, which tells the pipeline that it is allowed to split the data into as many pieces as it wants. Be careful that the pipeline also uses pieces to represent streaming data pieces, which is confusing, I am not considering
this case here. data paralle pieces are not quite the same as streaming pieces. we’re talking data parallel now.<o:p></o:p></span></p>
<p class="MsoListParagraph" style="text-indent:-18.0pt;mso-list:l0 level1 lfo1"><![if !supportLists]><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><span style="mso-list:Ignore">3)<span style="font:7.0pt "Times New Roman"">
</span></span></span><![endif]><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">assignment of piece number is essentially MPI rank<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Hope this helps<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">JB<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><b><span lang="EN-US" style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span lang="EN-US" style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> paraview-developers-bounces@paraview.org [mailto:paraview-developers-bounces@paraview.org]
<b>On Behalf Of </b>Jie Chen<br>
<b>Sent:</b> 14 February 2012 17:38<br>
<b>To:</b> paraview-developers@paraview.org<br>
<b>Subject:</b> [Paraview-developers] How does ParaView schedule render tasks among all the processes?<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><br clear="all">
<o:p></o:p></p>
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<p class="MsoNormal">Hi all,<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">I have installed the ParaView-3.12.0 on a cluster with MPI enabled. And I use it in a client-server mode.(pvserver is running on the cluster)<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">I'm curious about how ParaView process a task parallelly. The following is my questions:<o:p></o:p></p>
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<p class="MsoNormal">(1) How does ParaView split a file into multi-pieces for parallel processing, and how to combine the results together? Is there any special process which handles these splitting and combining works?<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">(2) What policy does ParaView use when it computes the number of pieces? <o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">(3)What policy does ParaView use when it assign the pieces to all the processes?<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">I'm just beginning to look into the ParaView source code. Hope somebody can give me some clue.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Thanks<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Jie<o:p></o:p></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt"><o:p> </o:p></p>
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