crobibero · Jun 27, 2026 · Jun 25, 2026 · Jun 26, 2026
diff --git a/Emby.Server.Implementations/ScheduledTasks/Tasks/OptimizeDatabaseTask.cs b/Emby.Server.Implementations/ScheduledTasks/Tasks/OptimizeDatabaseTask.cs
@@ -3,6 +3,7 @@
 using System.Threading;
 using System.Threading.Tasks;
 using Jellyfin.Database.Implementations;
+using MediaBrowser.Controller.Library;
 using MediaBrowser.Model.Globalization;
 using MediaBrowser.Model.Tasks;
 using Microsoft.Extensions.Logging;
@@ -17,21 +18,25 @@ public class OptimizeDatabaseTask : IScheduledTask, IConfigurableScheduledTask
     private readonly ILogger<OptimizeDatabaseTask> _logger;
     private readonly ILocalizationManager _localization;
     private readonly IJellyfinDatabaseProvider _jellyfinDatabaseProvider;
+    private readonly ILibraryManager _libraryManager;
 
     /// <summary>
     /// Initializes a new instance of the <see cref="OptimizeDatabaseTask" /> class.
     /// </summary>
     /// <param name="logger">Instance of the <see cref="ILogger"/> interface.</param>
     /// <param name="localization">Instance of the <see cref="ILocalizationManager"/> interface.</param>
     /// <param name="jellyfinDatabaseProvider">Instance of the JellyfinDatabaseProvider that can be used for provider specific operations.</param>
+    /// <param name="libraryManager">Instance of the <see cref="ILibraryManager"/> interface.</param>
     public OptimizeDatabaseTask(
         ILogger<OptimizeDatabaseTask> logger,
         ILocalizationManager localization,
-        IJellyfinDatabaseProvider jellyfinDatabaseProvider)
+        IJellyfinDatabaseProvider jellyfinDatabaseProvider,
+        ILibraryManager libraryManager)
     {
         _logger = logger;
         _localization = localization;
         _jellyfinDatabaseProvider = jellyfinDatabaseProvider;
+        _libraryManager = libraryManager;
     }
 
     /// <inheritdoc />
@@ -68,6 +73,15 @@ public IEnumerable<TaskTriggerInfo> GetDefaultTriggers()
     /// <inheritdoc />
     public async Task ExecuteAsync(IProgress<double> progress, CancellationToken cancellationToken)
     {
+        // Vacuuming/checkpointing requires an exclusive lock on the database. Running it while a library scan is in
+        // progress causes both operations to contend for the database and can stall the scan, so defer optimization
+        // until no scan is running. The task will run again on its next trigger.
+        if (_libraryManager.IsScanRunning)
+        {
+            _logger.LogInformation("Skipping database optimization because a library scan is currently running.");
+            return;
+        }
+
         _logger.LogInformation("Optimizing and vacuuming jellyfin.db...");
 
         try

diff --git a/Emby.Server.Implementations/ScheduledTasks/Tasks/PeopleValidationTask.cs b/Emby.Server.Implementations/ScheduledTasks/Tasks/PeopleValidationTask.cs
@@ -9,6 +9,7 @@
 using MediaBrowser.Model.Globalization;
 using MediaBrowser.Model.Tasks;
 using Microsoft.EntityFrameworkCore;
+using Microsoft.Extensions.Logging;
 
 namespace Emby.Server.Implementations.ScheduledTasks.Tasks;
 
@@ -20,18 +21,21 @@ public class PeopleValidationTask : IScheduledTask, IConfigurableScheduledTask
     private readonly ILibraryManager _libraryManager;
     private readonly ILocalizationManager _localization;
     private readonly IDbContextFactory<JellyfinDbContext> _dbContextFactory;
+    private readonly ILogger<PeopleValidationTask> _logger;
 
     /// <summary>
     /// Initializes a new instance of the <see cref="PeopleValidationTask" /> class.
     /// </summary>
     /// <param name="libraryManager">Instance of the <see cref="ILibraryManager"/> interface.</param>
     /// <param name="localization">Instance of the <see cref="ILocalizationManager"/> interface.</param>
     /// <param name="dbContextFactory">Instance of the <see cref="IDbContextFactory{TContext}"/> interface.</param>
-    public PeopleValidationTask(ILibraryManager libraryManager, ILocalizationManager localization, IDbContextFactory<JellyfinDbContext> dbContextFactory)
+    /// <param name="logger">Instance of the <see cref="ILogger{TCategoryName}"/> interface.</param>
+    public PeopleValidationTask(ILibraryManager libraryManager, ILocalizationManager localization, IDbContextFactory<JellyfinDbContext> dbContextFactory, ILogger<PeopleValidationTask> logger)
     {
         _libraryManager = libraryManager;
         _localization = localization;
         _dbContextFactory = dbContextFactory;
+        _logger = logger;
     }
 
     /// <inheritdoc />
@@ -71,6 +75,14 @@ public IEnumerable<TaskTriggerInfo> GetDefaultTriggers()
     /// <inheritdoc />
     public async Task ExecuteAsync(IProgress<double> progress, CancellationToken cancellationToken)
     {
+        // People validation performs heavy database writes that contend with an active library scan.
+        // Defer it until the scan has finished; the task will run again on its next trigger.
+        if (_libraryManager.IsScanRunning)
+        {
+            _logger.LogInformation("Skipping people validation because a library scan is currently running.");
+            return;
+        }
+
         IProgress<double> subProgress = new Progress<double>((val) => progress.Report(val / 2));
         await _libraryManager.ValidatePeopleAsync(subProgress, cancellationToken).ConfigureAwait(false);
 

diff --git a/Jellyfin.Server.Implementations/FullSystemBackup/BackupService.cs b/Jellyfin.Server.Implementations/FullSystemBackup/BackupService.cs
@@ -12,6 +12,7 @@
 using Jellyfin.Server.Implementations.StorageHelpers;
 using Jellyfin.Server.Implementations.SystemBackupService;
 using MediaBrowser.Controller;
+using MediaBrowser.Controller.Library;
 using MediaBrowser.Controller.SystemBackupService;
 using Microsoft.EntityFrameworkCore;
 using Microsoft.EntityFrameworkCore.Infrastructure;
@@ -33,6 +34,7 @@ public class BackupService : IBackupService
     private readonly IServerApplicationPaths _applicationPaths;
     private readonly IJellyfinDatabaseProvider _jellyfinDatabaseProvider;
     private readonly IHostApplicationLifetime _hostApplicationLifetime;
+    private readonly ILibraryManager _libraryManager;
     private static readonly JsonSerializerOptions _serializerSettings = new JsonSerializerOptions(JsonSerializerDefaults.General)
     {
         AllowTrailingCommas = true,
@@ -50,20 +52,23 @@ public class BackupService : IBackupService
     /// <param name="applicationPaths">The application paths.</param>
     /// <param name="jellyfinDatabaseProvider">The Jellyfin database Provider in use.</param>
     /// <param name="applicationLifetime">The SystemManager.</param>
+    /// <param name="libraryManager">Instance of the <see cref="ILibraryManager"/> interface.</param>
     public BackupService(
         ILogger<BackupService> logger,
         IDbContextFactory<JellyfinDbContext> dbProvider,
         IServerApplicationHost applicationHost,
         IServerApplicationPaths applicationPaths,
         IJellyfinDatabaseProvider jellyfinDatabaseProvider,
-        IHostApplicationLifetime applicationLifetime)
+        IHostApplicationLifetime applicationLifetime,
+        ILibraryManager libraryManager)
     {
         _logger = logger;
         _dbProvider = dbProvider;
         _applicationHost = applicationHost;
         _applicationPaths = applicationPaths;
         _jellyfinDatabaseProvider = jellyfinDatabaseProvider;
         _hostApplicationLifetime = applicationLifetime;
+        _libraryManager = libraryManager;
     }
 
     /// <inheritdoc/>
@@ -263,6 +268,14 @@ private bool TestBackupVersionCompatibility(Version backupEngineVersion)
     /// <inheritdoc/>
     public async Task<BackupManifestDto> CreateBackupAsync(BackupOptionsDto backupOptions)
     {
+        // Creating a backup runs a database optimization and reads the entire database under a transaction, both of
+        // which heavily contend with an active library scan and could capture an inconsistent database state.
+        if (_libraryManager.IsScanRunning)
+        {
+            _logger.LogWarning("Cannot create a backup while a library scan is running.");
+            throw new InvalidOperationException("Cannot create a backup while a library scan is running. Please try again once the scan has finished.");
+        }
+
         var manifest = new BackupManifest()
         {
             DateCreated = DateTime.UtcNow,