perf(memory): add reclaim signals and cache controls (#2689)

crates/scanner/src/lib.rs

@@ -32,3 +32,26 @@ pub use data_usage_define::*;
 pub use error::ScannerError;
 pub use scanner::init_data_scanner;
 pub use sleeper::{DynamicSleeper, SCANNER_IDLE_MODE, SCANNER_SLEEPER};
+use std::sync::atomic::{AtomicU64, Ordering};
+
+static SCANNER_ACTIVE_WORK_UNITS: AtomicU64 = AtomicU64::new(0);
+
+pub fn current_scanner_activity() -> u64 {
+    SCANNER_ACTIVE_WORK_UNITS.load(Ordering::Relaxed)
+}
+
+pub(crate) struct ScannerActivityGuard;
+
+impl ScannerActivityGuard {
+    pub(crate) fn new() -> Self {
+        SCANNER_ACTIVE_WORK_UNITS.fetch_add(1, Ordering::Relaxed);
+        Self
+    }
+}
+
+impl Drop for ScannerActivityGuard {
+    fn drop(&mut self) {
+        let _ = SCANNER_ACTIVE_WORK_UNITS
+            .fetch_update(Ordering::Relaxed, Ordering::Relaxed, |current| Some(current.saturating_sub(1)));
+    }
+}

crates/scanner/src/scanner.rs

@@ -18,7 +18,7 @@ use crate::data_usage_define::{BACKGROUND_HEAL_INFO_PATH, DATA_USAGE_BLOOM_NAME_
 use crate::scanner_folder::data_usage_update_dir_cycles;
 use crate::scanner_io::ScannerIO;
 use crate::sleeper::SCANNER_SLEEPER;
-use crate::{DataUsageInfo, ScannerError};
+use crate::{DataUsageInfo, ScannerActivityGuard, ScannerError};
 use chrono::{DateTime, Utc};
 use rustfs_common::heal_channel::HealScanMode;
 use rustfs_common::metrics::{CurrentCycle, Metric, Metrics, emit_scan_cycle_complete, global_metrics};
@@ -183,6 +183,7 @@ fn get_lock_acquire_timeout() -> Duration {
 
 #[instrument(skip_all)]
 async fn run_data_scanner_cycle(ctx: &CancellationToken, storeapi: &Arc<ECStore>, cycle_info: &mut CurrentCycle) {
+    let _activity_guard = ScannerActivityGuard::new();
     SCANNER_SLEEPER.refresh_from_env();
     info!("Start run data scanner cycle");
     cycle_info.current = cycle_info.next;
@@ -324,6 +325,7 @@ pub async fn store_data_usage_in_backend(
     let mut attempts = 1u32;
 
     while let Some(data_usage_info) = receiver.recv().await {
+        let _activity_guard = ScannerActivityGuard::new();
         if ctx.is_cancelled() {
             break;
         }