On Fri, Jan 17, 2020 at 4:03 PM Richard Henderson <address@hidden
With bad luck, we can wind up with no space at all for brk,
which will generally cause the guest malloc to fail.
The choice of 16MB is somewhat arbitrary. It's enough for libc
to get going, but without being so large that 32-bit guests or
32-bit hosts are in danger of running out of virtual address space.
It is expected that libc will be able to fall back to mmap arenas
after the limited brk space is exhausted.
The biggest abuser of brk() is emacs, so according to one old wag
this should be 80MB. Eighty Megabytes And Continuously Swapping.
Sorry that I don't have anything constructive to add.