improve concurrency handling for inventory job

db/helpers.go

@@ -149,7 +149,7 @@ func TableHasRows(ctx context.Context, dbConn *sqlx.DB, table string) (bool, err
 		ctx = context.Background()
 	}
 	var cancel context.CancelFunc
-	ctx, cancel = context.WithTimeout(ctx, 15*time.Second)
+	ctx, cancel = context.WithTimeout(ctx, 5*time.Second)
 	defer cancel()
 	query := fmt.Sprintf(`SELECT 1 FROM %s LIMIT 1`, table)
 	var exists int

internal/tasks/inventoryHelpers.go

@@ -44,8 +44,8 @@ func boolStringFromInterface(value interface{}) string {
 }
 
 // latestHourlySnapshotBefore finds the most recent hourly snapshot table prior to the given time, skipping empty tables.
-func latestHourlySnapshotBefore(ctx context.Context, dbConn *sqlx.DB, cutoff time.Time) (string, error) {
-	tables, err := listLatestHourlyWithRows(ctx, dbConn, "", cutoff.Unix(), 1, nil)
+func latestHourlySnapshotBefore(ctx context.Context, dbConn *sqlx.DB, cutoff time.Time, logger *slog.Logger) (string, error) {
+	tables, err := listLatestHourlyWithRows(ctx, dbConn, "", cutoff.Unix(), 1, logger)
 	if err != nil {
 		return "", err
 	}
@@ -103,7 +103,7 @@ LIMIT ?
 			continue
 		}
 		probed := false
-		hasRows := true
+		hasRows := count.Valid && count.Int64 > 0
 		start := time.Now()
 		if !count.Valid {
 			probed = true
@@ -141,12 +141,12 @@ LIMIT ?
 	return out, nil
 }
 
-// SnapshotTooSoon reports whether the gap between prev and curr is significantly shorter than expected (default: <50% interval).
+// SnapshotTooSoon reports whether the gap between prev and curr is significantly shorter than expected.
 func SnapshotTooSoon(prevUnix, currUnix int64, expectedSeconds int64) bool {
 	if prevUnix == 0 || currUnix == 0 || expectedSeconds <= 0 {
 		return false
 	}
-	return currUnix-prevUnix < expectedSeconds/2
+	return currUnix-prevUnix < expectedSeconds
 }
 
 // querySnapshotRows builds a SELECT with proper rebind for the given table/columns/where.

internal/tasks/inventoryLifecycle.go

@@ -137,10 +137,16 @@ ORDER BY snapshot_time ASC
 		if err := db.ValidateTableName(t.Table); err != nil {
 			continue
 		}
+		if t.Count.Valid {
+			if t.Count.Int64 <= 0 {
+				continue
+			}
+		} else {
 			hasRows, err := db.TableHasRows(ctx, dbConn, t.Table)
 			if err != nil || !hasRows {
 				continue
 			}
+		}
 		tables = append(tables, t)
 	}
 	return tables, nil

internal/tasks/inventorySnapshots.go

@@ -25,6 +25,16 @@ import (
 
 type ctxLoggerKey struct{}
 
+func loggerFromCtx(ctx context.Context, fallback *slog.Logger) *slog.Logger {
+	if ctx == nil {
+		return fallback
+	}
+	if l, ok := ctx.Value(ctxLoggerKey{}).(*slog.Logger); ok && l != nil {
+		return l
+	}
+	return fallback
+}
+
 // RunVcenterSnapshotHourly records hourly inventory snapshots into a daily table.
 // If force is true, any in-progress marker will be cleared before starting (useful for manual recovery).
 func (c *CronTask) RunVcenterSnapshotHourly(ctx context.Context, logger *slog.Logger, force bool) (err error) {
@@ -992,7 +1002,7 @@ func (c *CronTask) captureHourlySnapshotForVcenter(ctx context.Context, startTim
 	// If VM count dropped versus totals and we still haven't marked missing, try another comparison + wider event window.
 	if missingCount == 0 && prevVmCount.Valid && prevVmCount.Int64 > int64(totals.VmCount) {
 		// Fallback: compare against latest registered snapshot table.
-		if prevTable, err := latestHourlySnapshotBefore(ctx, dbConn, startTime); err == nil && prevTable != "" {
+		if prevTable, err := latestHourlySnapshotBefore(ctx, dbConn, startTime, loggerFromCtx(ctx, c.Logger)); err == nil && prevTable != "" {
 			moreMissing := c.markMissingFromPrevious(ctx, dbConn, prevTable, url, startTime, presentSnapshots, presentByUuid, presentByName, inventoryByVmID, inventoryByUuid, inventoryByName)
 			if moreMissing > 0 {
 				missingCount += moreMissing
@@ -1104,7 +1114,7 @@ func (c *CronTask) compareWithPreviousSnapshot(
 	inventoryByName map[string]queries.Inventory,
 	missingCount int,
 ) (string, int, int) {
-	prevTableName, prevTableErr := latestHourlySnapshotBefore(ctx, dbConn, startTime)
+	prevTableName, prevTableErr := latestHourlySnapshotBefore(ctx, dbConn, startTime, loggerFromCtx(ctx, c.Logger))
 	if prevTableErr != nil {
 		c.Logger.Warn("failed to locate previous hourly snapshot for deletion comparison", "error", prevTableErr, "url", url)
 	}
@@ -1115,8 +1125,8 @@ func (c *CronTask) compareWithPreviousSnapshot(
 	if prevTableName != "" {
 		moreMissing := c.markMissingFromPrevious(ctx, dbConn, prevTableName, url, startTime, presentSnapshots, presentByUuid, presentByName, inventoryByVmID, inventoryByUuid, inventoryByName)
 		missingCount += moreMissing
-		expectedSeconds := int64(durationFromSeconds(c.Settings.Values.Settings.VcenterInventorySnapshotSeconds, time.Hour).Seconds())
-		// Skip only if snapshots are much closer together than the configured cadence (e.g., rerun inside half interval).
+		expectedSeconds := int64(c.Settings.Values.Settings.VcenterInventorySnapshotSeconds)
+		// Skip only if snapshots are much closer together than the configured cadence.
 		if SnapshotTooSoon(prevSnapshotTime, startTime.Unix(), expectedSeconds) {
 			c.Logger.Info("skipping new-VM detection because snapshots are too close together", "prev_table", prevTableName, "prev_snapshot_unix", prevSnapshotTime, "current_snapshot_unix", startTime.Unix(), "expected_interval_seconds", expectedSeconds)
 		} else {