On 1/23/15 5:42 AM, Amit Kapila wrote:
*Fixed-Chunks*  
*No. of workers/Time (ms)*
>            *0*     *2*     *4*     *8*     *16*    *24*    *32*
Run-1   250536  266279  251263  234347  87930   50474   35474
Run-2   249587  230628  225648  193340  83036   35140   9100
Run-3   234963  220671  230002  256183  105382  62493   27903
Run-4   239111  245448  224057  189196  123780  63794   24746
Run-5   239937  222820  219025  220478  114007  77965   39766



The trend remains same although there is some variation.
In block-by-block approach, it performance dips (execution takes
more time) with more number of workers, though it stabilizes at
some higher value, still I feel it is random as it leads to random
scan.
In Fixed-chunk approach, the performance improves with more
number of workers especially at slightly higher worker count.

Those fixed chunk numbers look pretty screwy. 2, 4 and 8 workers make no 
difference, then suddenly 16 cuts times by 1/2 to 1/3? Then 32 cuts time by 
another 1/2 to 1/3?
--
Jim Nasby, Data Architect, Blue Treble Consulting
Data in Trouble? Get it in Treble! http://BlueTreble.com


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