Depends what you mean by 'deterministic' I suppose. Basically the system they're describing assigns a fixed time slice to the collector. In that way, yes it is deterministic in that the application is guaranteed to have the remaining processor time.
What isn't deterministic is the load on the collector. That is determined both by the rate at which your application generates garbage as it performs its work, and how that garbage generation lines up with the collector's time slices.
Under normal circumstances that load should have no affect on your application's behaviour or response times. But unlike a regular collector, this one will not degrade gracefully (becoming steadily slower as GC load increases): it will work 100% normal until it reaches a breaking point, at which time it will fail catastrophically.
What isn't deterministic is the load on the collector. That is determined both by the rate at which your application generates garbage as it performs its work, and how that garbage generation lines up with the collector's time slices.
Under normal circumstances that load should have no affect on your application's behaviour or response times. But unlike a regular collector, this one will not degrade gracefully (becoming steadily slower as GC load increases): it will work 100% normal until it reaches a breaking point, at which time it will fail catastrophically.