Add Env Var to disable second level cache

This is an attempt to track down possible causes of remaining database lockups. Add an environment variable to disable the second-level cache entirely to see if it works better on systems that still experience lockups.

Signed-off-by: gnattu <gnattuoc@me.com>

MediaBrowser.Controller/Extensions/ConfigurationExtensions.cs

@@ -64,6 +64,11 @@ namespace MediaBrowser.Controller.Extensions
         /// </summary>
         public const string SqliteCacheSizeKey = "sqlite:cacheSize";
 
+        /// <summary>
+        /// Disable second level cache of sqlite.
+        /// </summary>
+        public const string SqliteDisableSecondLevelCacheKey = "sqlite:disableSecondLevelCache";
+
         /// <summary>
         /// Gets a value indicating whether the application should host static web content from the <see cref="IConfiguration"/>.
         /// </summary>
@@ -128,5 +133,26 @@ namespace MediaBrowser.Controller.Extensions
         /// <returns>The sqlite cache size.</returns>
         public static int? GetSqliteCacheSize(this IConfiguration configuration)
             => configuration.GetValue<int?>(SqliteCacheSizeKey);
+
+        /// <summary>
+        /// Gets whether second level cache disabled from the <see cref="IConfiguration" />.
+        /// </summary>
+        /// <param name="configuration">The configuration to read the setting from.</param>
+        /// <returns>Whether second level cache disabled.</returns>
+        public static bool GetSqliteSecondLevelCacheDisabled(this IConfiguration configuration)
+        {
+            var disableSecondLevelCacheConfig = configuration.GetValue<string?>(SqliteDisableSecondLevelCacheKey);
+            var disableSecondLevelCache = false;
+            if (disableSecondLevelCacheConfig is not null)
+            {
+                disableSecondLevelCache = disableSecondLevelCacheConfig.ToUpperInvariant() switch
+                {
+                    "FALSE" or "NO" or "0" => false,
+                    _ => true
+                };
+            }
+
+            return disableSecondLevelCache;
+        }
     }
 }