root / man / man3 / HPL_pdlaswp00T.3
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.TH HPL_pdlaswp00T 3 "September 10, 2008" "HPL 2.0" "HPL Library Functions" |
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.SH NAME |
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HPL_pdlaswp00T \- Broadcast a column panel L and swap the row panel U. |
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.SH SYNOPSIS |
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\fB\&#include "hpl.h"\fR |
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|
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\fB\&void\fR |
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\fB\&HPL_pdlaswp00T(\fR |
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\fB\&HPL_T_panel *\fR |
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\fI\&PBCST\fR, |
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\fB\&int *\fR |
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\fI\&IFLAG\fR, |
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\fB\&HPL_T_panel *\fR |
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\fI\&PANEL\fR, |
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\fB\&const int\fR |
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\fI\&NN\fR |
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\fB\&);\fR |
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.SH DESCRIPTION |
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\fB\&HPL_pdlaswp00T\fR |
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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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|
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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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|
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log_2(P) * (lat + NB*LocQ(N) / bdwth) |
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|
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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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.SH ARGUMENTS |
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.TP 8 |
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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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.TP 8 |
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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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.TP 8 |
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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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.TP 8 |
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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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.SH SEE ALSO |
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.BR HPL_pdgesv \ (3), |
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.BR HPL_pdgesvK2 \ (3), |
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.BR HPL_pdupdateNT \ (3), |
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.BR HPL_pdupdateTT \ (3), |
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.BR HPL_pipid \ (3), |
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.BR HPL_plindx0 \ (3), |
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.BR HPL_dlaswp01T \ (3), |
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.BR HPL_dlaswp02N \ (3), |
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.BR HPL_dlaswp03T \ (3), |
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.BR HPL_dlaswp04T \ (3), |
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.BR HPL_dlaswp05T \ (3). |