1 files changed, 50 insertions, 1 deletions
diff --git a/MediaBrowser.Controller/BaseItemManager/BaseItemManager.cs b/MediaBrowser.Controller/BaseItemManager/BaseItemManager.cs
index 67aa7f338..085f769d0 100644
--- a/MediaBrowser.Controller/BaseItemManager/BaseItemManager.cs
+++ b/MediaBrowser.Controller/BaseItemManager/BaseItemManager.cs
@@ -1,5 +1,7 @@
-using System;
+using System;
 using System.Linq;
+using System.Threading;
+using MediaBrowser.Common.Configuration;
 using MediaBrowser.Controller.Channels;
 using MediaBrowser.Controller.Configuration;
 using MediaBrowser.Controller.Entities;
@@ -12,6 +14,8 @@ namespace MediaBrowser.Controller.BaseItemManager
     {
         private readonly IServerConfigurationManager _serverConfigurationManager;
 
+        private int _metadataRefreshConcurrency = 0;
+
         /// <summary>
         /// Initializes a new instance of the <see cref="BaseItemManager"/> class.
         /// </summary>
@@ -19,9 +23,17 @@ namespace MediaBrowser.Controller.BaseItemManager
         public BaseItemManager(IServerConfigurationManager serverConfigurationManager)
         {
             _serverConfigurationManager = serverConfigurationManager;
+
+            _metadataRefreshConcurrency = GetMetadataRefreshConcurrency();
+            SetupMetadataThrottler();
+
+            _serverConfigurationManager.ConfigurationUpdated += OnConfigurationUpdated;
         }
 
         /// <inheritdoc />
+        public SemaphoreSlim MetadataRefreshThrottler { get; private set; }
+
+        /// <inheritdoc />
         public bool IsMetadataFetcherEnabled(BaseItem baseItem, LibraryOptions libraryOptions, string name)
         {
             if (baseItem is Channel)
@@ -82,5 +94,42 @@ namespace MediaBrowser.Controller.BaseItemManager
 
             return itemConfig == null || !itemConfig.DisabledImageFetchers.Contains(name, StringComparer.OrdinalIgnoreCase);
         }
+
+        /// <summary>
+        /// Called when the configuration is updated.
+        /// It will refresh the metadata throttler if the relevant config changed.
+        /// </summary>
+        private void OnConfigurationUpdated(object sender, EventArgs e)
+        {
+            int newMetadataRefreshConcurrency = GetMetadataRefreshConcurrency();
+            if (_metadataRefreshConcurrency != newMetadataRefreshConcurrency)
+            {
+                _metadataRefreshConcurrency = newMetadataRefreshConcurrency;
+                SetupMetadataThrottler();
+            }
+        }
+
+        /// <summary>
+        /// Creates the metadata refresh throttler.
+        /// </summary>
+        private void SetupMetadataThrottler()
+        {
+            MetadataRefreshThrottler = new SemaphoreSlim(_metadataRefreshConcurrency);
+        }
+
+        /// <summary>
+        /// Returns the metadata refresh concurrency.
+        /// </summary>
+        private int GetMetadataRefreshConcurrency()
+        {
+            var concurrency = _serverConfigurationManager.Configuration.LibraryMetadataRefreshConcurrency;
+
+            if (concurrency <= 0)
+            {
+                concurrency = Environment.ProcessorCount;
+            }
+
+            return concurrency;
+        }
     }
 }