mache.parallel.system.ParallelSystem.placement_support

property ParallelSystem.placement_support: PlacementSupport

The placement mechanism available on this machine.

A caller that wants to run several launches at once inside one allocation should check this first: on a machine that reports PlacementSupport.NONE, concurrent launches will oversubscribe or serialize rather than run side by side.

This is determined from the launcher actually present rather than from the machine’s config, since a site can be upgraded across a launcher change without its mache config changing, and a stale assumption there fails in the worst way – the command is accepted and the placement silently does nothing.