A tunable name is split into three components, a top namespace, a tunable
namespace and the tunable name. The top namespace for tunables implemented in
the GNU C Library is glibc. Distributions that choose to add custom tunables
in their maintained versions of the GNU C Library may choose to do so under their own
top namespace.
The tunable namespace is a logical grouping of tunables in a single module. This currently holds no special significance, although that may change in the future.
The tunable name is the actual name of the tunable. It is possible that different tunable namespaces may have tunables within them that have the same name, likewise for top namespaces. Hence, we only support identification of tunables by their full name, i.e. with the top namespace, tunable namespace and tunable name, separated by periods.