Hello, sorry for my late answer ( i wrote the code friday but i could only debug today, being busy and on travel last week-end)
i modified my code to works with 'futures' , the speed is now incredible !!! (and it computes exact) the speed seems multiplied by even more than the number of CPUs (6): cat /proc/cpuinfo | grep processor processor : 0 processor : 1 processor : 2 processor : 3 processor : 4 processor : 5 https://github.com/damien-mattei/library-FunctProg/blob/master/guile/logiki%2B.scm#L1900 (declare minterms-vector unified-minterms-vector-1) (define (funct-unify-minterms-set-1-unit-future set1 set2) {function-unify-minterms-list <+ (λ (L) (apply function-unify-two-minterms-and-tag L))} ;; note : sorting is useless {minterms-set <+ (product-set-with-set-imperative-sorted set1 set2)} ;;(product-set-with-set-imperative set1 set2)} ;;(product-set-with-set set1 set2)} ;;(associate-set-with-set set1 set2)} ;; set multiplication : create list of pair of minterms {minterms-vector <- (list->vector minterms-set)} {minterms-vector-length <+ (vector-length minterms-vector)} {nb-procs <+ (current-processor-count)} {segmts <+ (segment 0 {minterms-vector-length - 1} nb-procs)} ;; compute the segments {unified-minterms-vector-1 <- (make-vector minterms-vector-length #f)} (run-in-parallel segmts proc-unify-minterms-seg) ;; run the parallel code {unified-minterms-set-1 <+ (vector->list unified-minterms-vector-1)} {unified-minterms-set-2 <+ (filter (λ (x) x) unified-minterms-set-1)} ;; remove #f results {unified-minterms-set <+ (remove-duplicates-sorted unified-minterms-set-2)} ;; uniq unified-minterms-set) i keeped your 'segment' definitions to index an array of data after convert it from list to vector (list->vector) which probably consume additional time on big data list ( i had more than 1000000 element list lengths at some point) i used a simplified version of run-in parallel (that do not do 'reduce after processing data): https://github.com/damien-mattei/library-FunctProg/blob/master/guile/logiki%2B.scm#L1794 the computation on a segment is done by those functions: https://github.com/damien-mattei/library-FunctProg/blob/master/guile/logiki%2B.scm#L1842 {function-unify-minterms-list <+ (λ (L) (apply function-unify-two-minterms-and-tag L))} ;; proc to be called with futures (define (proc-unify-minterms-seg seg) {start <+ (segment-start seg)} {end <+ (segment-end seg)} (for ({i <+ start} {i <= end} {i <- {i + 1}}) {mtL <+ {minterms-vector[i]}} {unified-minterms-vector-1[i] <- (function-unify-minterms-list mtL)})) i use those code in another program symbolically to compute a value named Cn: C0 = T C1 = T C2 = T C3 = (B1 ∨ B2) C4 = (B2 ∨ (B1 ∧ B3)) C5 = ((B1 ∧ B3) ∨ (B2 ∧ B3) ∨ (B2 ∧ B4) ∨ (B3 ∧ B4)) C6 = ((B1 ∧ B3 ∧ B5) ∨ (B2 ∧ B3 ∧ B5) ∨ (B2 ∧ B4) ∨ (B3 ∧ B4) ∨ (B4 ∧ B5)) C7 = ((B1 ∧ B3 ∧ B5) ∨ (B2 ∧ B3 ∧ B5) ∨ (B2 ∧ B4 ∧ B6) ∨ (B3 ∧ B4 ∧ B6) ∨ (B4 ∧ B5) ∨ (B5 ∧ B6)) C8 = ((B1 ∧ B3 ∧ B5 ∧ B7) ∨ (B2 ∧ B3 ∧ B5 ∧ B7) ∨ (B2 ∧ B4 ∧ B6) ∨ (B3 ∧ B4 ∧ B6) ∨ (B4 ∧ B5 ∧ B7) ∨ (B5 ∧ B6) ∨ (B6 ∧ B7)) C9 = ((B1 ∧ B3 ∧ B5 ∧ B7) ∨ (B2 ∧ B3 ∧ B5 ∧ B7) ∨ (B2 ∧ B4 ∧ B6 ∧ B8) ∨ (B3 ∧ B4 ∧ B6 ∧ B8) ∨ (B4 ∧ B5 ∧ B7) ∨ (B5 ∧ B6 ∧ B8) ∨ (B6 ∧ B7) ∨ (B7 ∧ B8)) from C1 to C9 used to be fast,less than a minute for the whole with or without // C10 = ((B1 ∧ B3 ∧ B5 ∧ B7 ∧ B9) ∨ (B2 ∧ B3 ∧ B5 ∧ B7 ∧ B9) ∨ (B2 ∧ B4 ∧ B6 ∧ B8) ∨ (B3 ∧ B4 ∧ B6 ∧ B8) ∨ (B4 ∧ B5 ∧ B7 ∧ B9) ∨ (B5 ∧ B6 ∧ B8) ∨ (B6 ∧ B7 ∧ B9) ∨ (B7 ∧ B8) ∨ (B8 ∧ B9)) C10 takes a few minutes but C11 used to take one day before // with 'future' and i got now the result during less than one hour!!! C11 = ((B1 ∧ B3 ∧ B5 ∧ B7 ∧ B9) ∨ (B10 ∧ B2 ∧ B4 ∧ B6 ∧ B8) ∨ (B10 ∧ B3 ∧ B4 ∧ B6 ∧ B8) ∨ (B10 ∧ B5 ∧ B6 ∧ B8) ∨ (B10 ∧ B7 ∧ B8) ∨ (B10 ∧ B9) ∨ (B2 ∧ B3 ∧ B5 ∧ B7 ∧ B9) ∨ (B4 ∧ B5 ∧ B7 ∧ B9) ∨ (B6 ∧ B7 ∧ B9) ∨ (B8 ∧ B9)) i never got C12 in the past ,even with 7 days of computation! and i got it today during the lunchbreak !!! C12 = ((B1 ∧ B11 ∧ B3 ∧ B5 ∧ B7 ∧ B9) ∨ (B10 ∧ B11) ∨ (B10 ∧ B2 ∧ B4 ∧ B6 ∧ B8) ∨ (B10 ∧ B3 ∧ B4 ∧ B6 ∧ B8) ∨ (B10 ∧ B5 ∧ B6 ∧ B8) ∨ (B10 ∧ B7 ∧ B8) ∨ (B10 ∧ B9) ∨ (B11 ∧ B2 ∧ B3 ∧ B5 ∧ B7 ∧ B9) ∨ (B11 ∧ B4 ∧ B5 ∧ B7 ∧ B9) ∨ (B11 ∧ B6 ∧ B7 ∧ B9) ∨ (B11 ∧ B8 ∧ B9)) (note that a wise people can find a general formula for Cn based on Cn-1 but that is another (mathematical) story....) i'm computing C13 but i see that it consumes 12gb out of 16gb of my system ! and stopped on the linux box : GC Warning: Repeated allocation of very large block (appr. size 510935040): May lead to memory leak and poor performance Processus arrêté but still running on the Mac laptop...ok will see that but i think that the data set is now huge and there is noting that can be done with that... note that there is still an hash table used in function-unify-two-minterms-and-tag and i will use another data structure and algo to avoid that, i feared that the concurrent access to hash table can cause the guile 'future' to crash or fails or to slow down the process but not! result is incredibly fast.Also i use continuation and i read it can cause problem with 'future' i will improve that too... I will see where i can improve the algo and data structure to optimize again but this is already really good. Thanks Damien On Fri, Oct 14, 2022 at 10:39 AM Zelphir Kaltstahl < zelphirkaltst...@posteo.de> wrote: > Hello Damien, > On 10/14/22 10:21, Damien Mattei wrote: > > yes Zelphir i think there is a problem in the threading part of guile, > whatever the code is ,it run well the first time, and after is unstable. > Long ago at the very begin of Java language on my master project at > university i experienced same problem with Java "green" threads, under > windows and/or linux ,i can't remember. > > I'm trying your code and future, which have perheaps also the portability > with other schemes, future can provide "light" // , with carefull code it > could be ok. > > in your segment.scm code ,is segment-count possibly replaced by the number > of available CPUs or nodes, if i understand well? > > Regards, > Damien > > Correct. For each segment one future is used. > > However, there are scenarios, where one would rather want to interleave > the numbers of the whole range, to have a "fairer" workload per future, for > example: > > (1 2 3 4 5 6 7 8 9) > > -> (1 4 7), (2 5 8), (3 6 9) > > instead of > > -> (1 2 3) (4 5 6) (7 8 9) > > (I seem to remember this to be the case for Mandelbrot set calculations, > but might be wrong.) > > But that is all a matter of forming some segments and what a segment is, > not really part of the logic of creating futures. So one could create then > in any way that fits ones use-case. I have not generalized that segment > logic that far, but it is doable. > > Anyway, if anyone more knowledgeable could chime in on what the > performance differences between futures and parallel map are, that would be > great! Or pointing out some flaws that this kind of future usage might > have. Or when the point is reached to switch to guile-fibers library. > > Regards, > Zelphir > > -- > repositories: https://notabug.org/ZelphirKaltstahl > >
