pub fn detect_memory_stall() -> Option<f64>Available on crate feature
memory only.Expand description
Memory PSI stall fraction: cgroup v2 memory.pressure some avg10, as a
0.0-1.0 fraction (avg10 is the percentage of the last 10s in which at
least one task stalled waiting on memory).
This is the earliest memory-pressure signal – it rises on reclaim/thrash before byte ratios cross a threshold. Exposed for observability (emit it as a gauge and alert on it); it is deliberately NOT folded into the scale/shed decision, because the stall-percent at which to act is workload-specific and wants per-service calibration, not a guessed constant.
None when PSI is unavailable (kernel < 4.20, PSI disabled, or cgroup v1).