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<TITLE>HPL_pdlaswp00N HPL 2.0 Library Functions September 10, 2008</TITLE> |
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<BODY BGCOLOR="WHITE" TEXT = "#000000" LINK = "#0000ff" VLINK = "#000099" |
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ALINK = "#ffff00"> |
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<H1>Name</H1> |
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<B>HPL_pdlaswp00N</B> Broadcast a column panel L and swap the row panel U. |
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<H1>Synopsis</H1> |
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<CODE>#include "hpl.h"</CODE><BR><BR> |
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<CODE>void</CODE> |
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<CODE>HPL_pdlaswp00N(</CODE> |
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<CODE>HPL_T_panel *</CODE> |
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<CODE>PBCST</CODE>, |
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<CODE>int *</CODE> |
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<CODE>IFLAG</CODE>, |
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<CODE>HPL_T_panel *</CODE> |
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<CODE>PANEL</CODE>, |
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<CODE>const int</CODE> |
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<CODE>NN</CODE> |
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<CODE>);</CODE> |
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<H1>Description</H1> |
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<B>HPL_pdlaswp00N</B> |
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applies the NB row interchanges to NN columns of the |
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trailing submatrix and broadcast a column panel. |
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Bi-directional exchange is used to perform the swap :: broadcast of |
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the row panel U at once, resulting in a lower number of messages than |
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usual as well as a lower communication volume. With P process rows and |
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assuming bi-directional links, the running time of this function can |
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be approximated by: |
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log_2(P) * (lat + NB*LocQ(N) / bdwth) |
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where NB is the number of rows of the row panel U, N is the global |
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number of columns being updated, lat and bdwth are the latency and |
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bandwidth of the network for double precision real words. Mono |
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directional links will double this communication cost. |
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<H1>Arguments</H1> |
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<PRE>
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PBCST (local input/output) HPL_T_panel * |
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On entry, PBCST points to the data structure containing the |
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panel (to be broadcast) information. |
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</PRE>
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<PRE>
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IFLAG (local input/output) int * |
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On entry, IFLAG indicates whether or not the broadcast has |
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already been completed. If not, probing will occur, and the |
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outcome will be contained in IFLAG on exit. |
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</PRE>
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<PRE>
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PANEL (local input/output) HPL_T_panel * |
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On entry, PANEL points to the data structure containing the |
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panel (to be broadcast and swapped) information. |
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</PRE>
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<PRE>
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NN (local input) const int |
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On entry, NN specifies the local number of columns of the |
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trailing submatrix to be swapped and broadcast starting at |
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the current position. NN must be at least zero. |
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</PRE>
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<H1>See Also</H1> |
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<A HREF="HPL_pdgesv.html">HPL_pdgesv</A>, |
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<A HREF="HPL_pdgesvK2.html">HPL_pdgesvK2</A>, |
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<A HREF="HPL_pdupdateNN.html">HPL_pdupdateNN</A>, |
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<A HREF="HPL_pdupdateTN.html">HPL_pdupdateTN</A>, |
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<A HREF="HPL_pipid.html">HPL_pipid</A>, |
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<A HREF="HPL_plindx0.html">HPL_plindx0</A>, |
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<A HREF="HPL_dlaswp01N.html">HPL_dlaswp01N</A>, |
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<A HREF="HPL_dlaswp02N.html">HPL_dlaswp02N</A>, |
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<A HREF="HPL_dlaswp03N.html">HPL_dlaswp03N</A>, |
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<A HREF="HPL_dlaswp04N.html">HPL_dlaswp04N</A>, |
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<A HREF="HPL_dlaswp05N.html">HPL_dlaswp05N</A>. |
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