i made the test, here is what i can tell you from my experiments 1) for a mapMatrix ( map<string, map<string, ex> > ) of 8524 x 8524 where all expression where 0, the RAM usage was 6GB ~ 18% of 32GB, very close to your stimation Alexei, you where right on that 2) however, if i repeat the experiment but let the expressions be what they should be (which are pretty large), then RAM usage goes beyond 32GB, i predict is something like 40GB of usage. 3) i would be complaining about the high ammount of RAM usage if it werent because of the following peculiarity. If instead of a mtrix, i decide to store the expresions in a system ecuation form with its corresponding variables (in the way that all elements of a row are grouped into one big polinomial expression), RAM usage is becomes low again! 2) and 3) have the same ammount of terms, just grouped in a different way, it is strange, i am gonna do some more tests and any news i will post back, Alexei, what is your opinion on my experience? On Fri, Oct 22, 2010 at 12:34 PM, Cristobal Navarro <axischire@gmail.com>wrote:
Alexei
thanks for helping,
i am going to do something equivalent to what you suggested, i will fill all expresions of the mapMatrix with zeros, and see how much RAM i consume because of the strings. ill post my results in a moment. best regards Cristobal
On Fri, Oct 22, 2010 at 9:53 AM, Alexei Sheplyakov < alexei.sheplyakov@gmail.com> wrote:
Hi again,
On Fri, Oct 22, 2010 at 12:22 AM, Cristobal Navarro <axischire@gmail.com> wrote:
i kept investigating, based on the test i've made, im almost sure, 99%, that the increase in memory usage is due to the segmentation of the expressions.
I don't think the problem has anything to do with GiNaC. Hint: try sticking ints (instead of ex*) into that map. Check the memory usage, and compare it with your calculations.
Use a different data structure (perhaps hash map or a sorted array), and store ex instead of pointers.
Best regards, Alexei _______________________________________________ GiNaC-list mailing list GiNaC-list@ginac.de https://www.cebix.net/mailman/listinfo/ginac-list