True, but zones and HeapAlloc do a fair bit of work to handle objects of multiple sizes. If you're partitioning up a page and you know every object on the page is 8 or 16 or 48 bytes, it's MUCH simpler. And a lot of the data structures in a compiler tend to be small-tens-of-bytes nodes. On Mon, Aug 17, 2020 at 3:28 PM Paul Winalski wrote: > On 8/17/20, Jim Geist wrote: > > When did mmap(2) come about? Another thing I've seen is building a small > > block allocator on top of that. You can guarantee that all your objects > are > > nicely collected into the same set of pages for locality with very little > > overhead. > > > mmap(2) certainly can be used to allocate blocks for the mini-heap > itself, but you still have to write your own equivalents of malloc() > and free() to allocate data structures within the mini-heap. The nice > thing about VMS heap zones and Microsoft's private heaps is that you > get the malloc()/free() layer off-the-shelf; you don't have to roll > your own. > > -Paul W. >