The backend allocator for the slab is a sliced heap, which hands out
allocations with page-size granularity (4096 bytes). Therefore, the
slab-block size should also be about a multiple of the page size minus
some bytes of overhead.
Additional adjustments:
- The slab-block size and the default quota-upgrade amount for SIGNAL
sessions depends on the platform bit width now.
- The signal test also stresses the case of many managed context in one
session including creation and destruction of the used signal receiver
in repeated rounds.
This patch changes the top-level directory layout as a preparatory
step for improving the tools for managing 3rd-party source codes.
The rationale is described in the issue referenced below.
Issue #1082
Christian Helmuth
Norman Feske