Well, I am sure that these algorithms can be parallelized, using 28.io, or other vendor solutions. However, honestly, today, you would have to spend tons of processors, watts, intelligence, to perform a matrix multiplication over a 4000x4000 matrix with JSONiq or XQUERY 3.0. I can compute such a multiplication within a second using BLAS over a single threaded process.
2014-02-03 Ghislain Fourny <[email protected]>: > Hi, > > With a naive parallelism approach (on $i and $j), I think it's possible to > bring it down to O(N) with a constant cost (in dollars), assuming "full > cloud elasticity" (i.e., the number of instances that can be triggered up > is not the bottleneck). > > The 28.io platform should supports this (disclaimer: it's my employer). > > Kind regards, > Ghislain > > > On 03 Feb 2014, at 12:30, jean-marc Mercier <[email protected]> > wrote: > > > Hi all, > > > > I've tried the following JSON query with zorba, mimicking a NxN, with > N=200, matrix multiplications. Time is 10 sec on http://try.zorba.io/, > behaving with a cubic N^3 complexitity. > > Do you really want to know what are the performances of standard linear > algebra library for such matrix multiplications ? > > > > > > > > > > import module namespace datetime = " > http://www.zorba-xquery.com/modules/datetime";; > > > > declare variable $size := 200; > > > > declare variable $A := [ for $i in 1 to $size return > > [ > > for $j in 1 to $size return $i*$size+$j > > ] > > ]; > > > > let $R := ( datetime:current-time(), > > [ > > for $i in 1 to count(jn:members($A)) return > > [ > > for $k in 1 to count(jn:members($A)) return > > fn:sum( > > for $j in 1 to count(jn:members($A)) return > > $A($i)($j) * $A($j)($k) > > ) > > ] > > ] > > , datetime:current-time() ) > > > > return $R[count($R)] - $R[1] > > > > > > 2014-02-03 David Carlisle <[email protected]>: > > On 03/02/2014 10:56, Hermann Stamm-Wilbrandt wrote: > > PT1.713634S (JSONiq) versus PT9.77805S (XQuery) > > > > > > ooh interesting , I wonder where the bottleneck in the xquery is. > > Probably as Michael commented at some point earlier in the thread, the > > time to access the ith element of a sequence $a[$i]. > > > > > > But the language doesn't _need_ to change, just if more people did it > > the xquery compilers would perhaps look out for sequences that are > > exclusively accessed via numeric filters and implement them in a way > > that gives constant time access. Having a separate array type does give > > them a big hint though:-) > > > > David > > > > > > ________________________________________________________________________ > > The Numerical Algorithms Group Ltd is a company registered in England > > and Wales with company number 1249803. The registered office is: > > Wilkinson House, Jordan Hill Road, Oxford OX2 8DR, United Kingdom. > > > > This e-mail has been scanned for all viruses by Star. The service is > > powered by MessageLabs. > ________________________________________________________________________ > > _______________________________________________ > > [email protected] > > http://x-query.com/mailman/listinfo/talk > > > > _______________________________________________ > > [email protected] > > http://x-query.com/mailman/listinfo/talk > >
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