On Sun, Jun 22, 2008 at 13:09, Burlen Loring <burlen.loring@xxxxxxxxxxx> wrote: > We have some complaints from our users that if we do not use > malloc/realloc/free inside our container class, and rather we use operator > new/delete, that we have heap fragmentation problem that leads to their > running out of memory. We have evidence that its true and additionally we > see that additionally realloc gives performance advantage. Is there anything > we can do to actively combat heap fragmentation when using new/delete? We > already do the simple things like double the current size of the container > if we need to extend. Can we tell the heap to de-fragment itself somehow? > Are there any tools for dynamically observing the state of the heap? Are we > "shooting our selves in the foot"(in terms of running out of memory) by > using malloc and new together in the same library? Are there any must read > books/documents that I should have read on this topic? > Well, it's simple for people to use a malloc/free allocator with containers, so I don't think that's a big problem. The only container where realloc could really be used is vector, but until we get new allocator concepts, that can be mostly mitigated by reserve. I don't think that the heap can de-fragment itself, since it doesn't know where the pointers are.
