On Tue, Apr 29, 2014 at 03:02:44PM +0400, Sergei Gorelkin wrote: > On 29.04.2014 14:37, Tomas Hajny wrote: > > >>>I don't know the reason of your difference, but no time necessary at all > >>>(0 ms) for the valgrind variant looks very suspicious to me. > >>But compiling by kylix compiler, i get the same results as by fpc with > >>-gv option in linux. > >>This is the reason why I start to hunt where is my program to slow if > >>compiled by fpc against kylix. > > > >Can't it be somehow related to the method used for measuring the time > >under Linux? Is the result shown inside consistent to the overall time > >necessary for the program run? > > > Time measurement appears to be correct. Strace shows that > reallocation happens using mremap syscalls, which apparently > rearranges pages within address space without actual moving the > data. This indeed can be done with almost zero overhead, but is > hardly portable.
Thanks for the fast and perfect explanation. Resolution for me is that heap manager cannot be multiplatformly improved. I do some optimatization in my code. Petr -- Petr Kristan . EPOS PRO s.r.o., Smilova 333, 530 02 Pardubice tel: +420 461101401 Czech Republic (Eastern Europe) fax: +420 461101481 _______________________________________________ fpc-devel maillist - [email protected] http://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-devel
