The threaded runtime appears to have trouble switching from high-usage threads. This behavior appears at its worst in Hans, in which traffic piles up in one layer without a context switch relieving the pressure on the intermediary channels. It's not clear if this is a problem in which we're not doing context switches across capabilities when we have a limited number of CPUs, or if there's a fundamental problem in how we're catching thread change signals from outside.
Actually, the fact that profiling works irregularly in the threaded runtime may suggest the latter.
The threaded runtime appears to have trouble switching from high-usage threads. This behavior appears at its worst in Hans, in which traffic piles up in one layer without a context switch relieving the pressure on the intermediary channels. It's not clear if this is a problem in which we're not doing context switches across capabilities when we have a limited number of CPUs, or if there's a fundamental problem in how we're catching thread change signals from outside.
Actually, the fact that profiling works irregularly in the threaded runtime may suggest the latter.