HPL residual check failure

Mon Sep 3 05:22:41 PDT 2001

Hi
When I was doing HPL benchmark test using big matrix(bigger than 20,000 ) with many linux server(more than 20), sometimes I got residual check error as attached. 
When I got residual check error, I turned off my linux servers for several hours and then tried again. And usually it worked - I don't know the reason.
Heat is suspicious. But, is it really heat problem?
Is there anybody who have experienced similar problem or know the reason?
please help me.

Thanks in advance! 

Keaton

HPL result files------------------------------------------------------------

============================================================================
T/V                N    NB     P     Q               Time             Gflops
----------------------------------------------------------------------------
W11R2C4        21000   200     6     6             702.80          8.786e+00
----------------------------------------------------------------------------
||Ax-b||_oo / ( eps * ||A||_1  * N        ) =        0.0272768 ...... PASSED
||Ax-b||_oo / ( eps * ||A||_1  * ||x||_1  ) =        0.0140749 ...... PASSED
||Ax-b||_oo / ( eps * ||A||_oo * ||x||_oo ) =        0.0026585 ...... PASSED
============================================================================
T/V                N    NB     P     Q               Time             Gflops
----------------------------------------------------------------------------
W11R2C4        23000   200     6     6             866.35          9.364e+00
----------------------------------------------------------------------------
||Ax-b||_oo / ( eps * ||A||_1  * N        ) =     3255.3898794 ...... FAILED
||Ax-b||_oo / ( eps * ||A||_1  * ||x||_1  ) =     7833.1904572 ...... FAILED
||Ax-b||_oo / ( eps * ||A||_oo * ||x||_oo ) =     1364.3123654 ...... FAILED
||Ax-b||_oo  . . . . . . . . . . . . . . . . . =           0.000049
||A||_oo . . . . . . . . . . . . . . . . . . . =        5827.145943
||A||_1  . . . . . . . . . . . . . . . . . . . =        5836.795619
||x||_oo . . . . . . . . . . . . . . . . . . . =           2.390054