apply healing per object at 1024 cycles (#18050)

- we already have MRF for most recent failures
- we trigger healing during HEAD/GET operation

These are enough, also change the default max wait
from 5sec to 1sec for default scanner speed.

cmd/data-scanner.go

@@ -55,10 +55,9 @@ const (
 	dataScannerStartDelay            = 1 * time.Minute                  // Time to wait on startup and between cycles.
 
 	healDeleteDangling   = true
-	healFolderIncludeProb = 32  // Include a clean folder one in n cycles.
+	healObjectSelectProb = 1024 // Overall probability of a file being scanned; one in n.
-	healObjectSelectProb  = 512 // Overall probability of a file being scanned; one in n.
 
-	dataScannerExcessiveVersionsThreshold = 1000  // Issue a warning when a single object has more versions than this
+	dataScannerExcessiveVersionsThreshold = 100   // Issue a warning when a single object has more versions than this
 	dataScannerExcessiveFoldersThreshold  = 50000 // Issue a warning when a folder has more subfolders than this in a *set*
 )
 
@@ -66,7 +65,7 @@ var (
 	globalHealConfig heal.Config
 
 	// Sleeper values are updated when config is loaded.
-	scannerSleeper = newDynamicSleeper(10, 10*time.Second, true)
+	scannerSleeper = newDynamicSleeper(2, time.Second, true) // Keep defaults same as config defaults
 	scannerCycle   = uatomic.NewDuration(dataScannerStartDelay)
 )
 
@@ -274,7 +273,6 @@ type folderScanner struct {
 // rarer if the bloom filter for the path is clean and no lifecycles are applied.
 // Skipped leaves have their totals transferred from the previous cycle.
 //
-// A clean leaf will be included once every healFolderIncludeProb for partial heal scans.
 // When selected there is a one in healObjectSelectProb that any object will be chosen for heal scan.
 //
 // Compaction happens when either:

internal/config/scanner/scanner.go

@@ -99,7 +99,7 @@ func LookupConfig(kvs config.KVS) (cfg Config, err error) {
 	case "fast":
 		cfg.Delay, cfg.MaxWait, cfg.Cycle = 1, 100*time.Millisecond, time.Minute
 	case "default":
-		cfg.Delay, cfg.MaxWait, cfg.Cycle = 2, 5*time.Second, time.Minute
+		cfg.Delay, cfg.MaxWait, cfg.Cycle = 2, time.Second, time.Minute
 	case "slow":
 		cfg.Delay, cfg.MaxWait, cfg.Cycle = 10, 15*time.Second, time.Minute
 	case "slowest":