Ironclad features two physical memory allocator choices for use, the chosen allocator will be used both for kernel and userland allocations, the standard and alloconly allocators.
The standard allocator is a general purpose allocator for your average everyday allocator needs. Its internally implemented as a bitmap allocator with page-sized blocks and a quick cache for small objects, along with some quick hardening features, like checksums.
The alloconly option features several optimizations on top of the usual allocator in order to save memory and tune operation, for usecases where nor userland nor the kernel are wanted to deallocate memory at all.