On 01/04/11 00:43, Bob Harris wrote: > OK, So, I conclude from that the presence of valgrind is contributing > to the failure of the test program. Possibly there is something about > my build that is different with valgrind than without that causes the > underlying heap allocator to behave differently. I note that the > failure occurs around 2.8G, which is reminiscent of where I ran into > allocation limitations on a different unix machine, a machine with 4G > of physical RAM and a 32-bit address, about a year ago. Could it be > that when I build for valgrind I'm somehow building in 32-bit mode > (recall that this is an x86_64 with 32G physical RAM). I've appended > my Makefile in case anyone can see something obvious from it (I'm not > using any IDE for this, just a bash shell and "make" from the command > line).
It's entirely expected that it may fail under valgrind when it doesn't normally because the memory layout is different plus every byte of memory you allocate has a little over a byte (nine bits) of overhead in the form of the shadow memory valgrind is using to track it, and so on. You will run out of memory more quickly under valgrind that you do normally is the basic message. Tom -- Tom Hughes ([email protected]) http://compton.nu/ ------------------------------------------------------------------------------ Create and publish websites with WebMatrix Use the most popular FREE web apps or write code yourself; WebMatrix provides all the features you need to develop and publish your website. http://p.sf.net/sfu/ms-webmatrix-sf _______________________________________________ Valgrind-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/valgrind-users
