Method read_files_with_priority

nodedb/src/data/io/uring_reader.rs:258–274

Priority-aware variant of [`read_files`]. Identical to `read_files` but records IO wait time in `metrics` under the bucket corresponding to `priority`: - `Background` / `Normal` → `TIER_LOW` - `High` → `TIER_HIGH` - `Critical` → `TIER_CRITICAL` The wait clock starts just before the first SQE submission and stops after all CQEs are reaped. File open + buffer setup

(
        &mut self,
        paths: &[&Path],
        priority: Priority,
        metrics: &IoMetrics,
    )

    /// after all CQEs are reaped.  File open + buffer setup time is included
    /// because it reflects the total latency seen by the caller.
    pub fn read_files_with_priority(
        &mut self,
        paths: &[&Path],
        priority: Priority,
        metrics: &IoMetrics,
    ) -> Vec<Vec<u8>> {
        let tier = match priority {
            Priority::Background | Priority::Normal => TIER_LOW,
            Priority::High => TIER_HIGH,
            Priority::Critical => TIER_CRITICAL,
        };
        let t0 = Instant::now();
        let result = self.read_files(paths);
        let wait_ns = t0.elapsed().as_nanos() as u64;
        metrics.record_wait(tier, wait_ns);
        result
    }
}

/// Tracks which buffer a read uses.