3 ms·
It depends on the hypervisor. XEN/AWS uses and older slower path for memory allocation then the modern KVM/Intel-EPT allows. Every `malloc` under XEN (that can
by valarauca1 9y ago
It depends on the hypervisor. XEN/AWS uses and older slower path for memory allocation then the modern KVM/Intel-EPT allows.
Every `malloc` under XEN (that can't be satisfied with unused memory already mapped into that processes userspace) requires a hyper call.
This VMM approach was _largely_ depreciated about 6 years ago when Intel created page table bits that let the bare metal OS give the VM a _range_ of memory it can virtually re-map, but AWS hasn't adopted this.