Add GC hints to prevent memory leaks from large byte arrays

allstarr/Controllers/AdminController.cs

@@ -1911,23 +1911,36 @@ public class AdminController : ControllerBase
     {
         try
         {
+            // Get memory stats BEFORE GC
+            var memoryBeforeGC = GC.GetTotalMemory(false);
+            var gen0Before = GC.CollectionCount(0);
+            var gen1Before = GC.CollectionCount(1);
+            var gen2Before = GC.CollectionCount(2);
+            
             // Force garbage collection to get accurate numbers
             GC.Collect();
             GC.WaitForPendingFinalizers();
             GC.Collect();
 
-            var memoryUsage = GC.GetTotalMemory(false);
+            var memoryAfterGC = GC.GetTotalMemory(false);
-            var gen0 = GC.CollectionCount(0);
+            var gen0After = GC.CollectionCount(0);
-            var gen1 = GC.CollectionCount(1);
+            var gen1After = GC.CollectionCount(1);
-            var gen2 = GC.CollectionCount(2);
+            var gen2After = GC.CollectionCount(2);
             
             // Get process memory info
             var process = System.Diagnostics.Process.GetCurrentProcess();
             
             return Ok(new {
                 Timestamp = DateTime.UtcNow,
-                GCMemoryBytes = memoryUsage,
+                BeforeGC = new {
-                GCMemoryMB = Math.Round(memoryUsage / (1024.0 * 1024.0), 2),
+                    GCMemoryBytes = memoryBeforeGC,
+                    GCMemoryMB = Math.Round(memoryBeforeGC / (1024.0 * 1024.0), 2)
+                },
+                AfterGC = new {
+                    GCMemoryBytes = memoryAfterGC,
+                    GCMemoryMB = Math.Round(memoryAfterGC / (1024.0 * 1024.0), 2)
+                },
+                MemoryFreedMB = Math.Round((memoryBeforeGC - memoryAfterGC) / (1024.0 * 1024.0), 2),
                 ProcessWorkingSetBytes = process.WorkingSet64,
                 ProcessWorkingSetMB = Math.Round(process.WorkingSet64 / (1024.0 * 1024.0), 2),
                 ProcessPrivateMemoryBytes = process.PrivateMemorySize64,
@@ -1935,9 +1948,15 @@ public class AdminController : ControllerBase
                 ProcessVirtualMemoryBytes = process.VirtualMemorySize64,
                 ProcessVirtualMemoryMB = Math.Round(process.VirtualMemorySize64 / (1024.0 * 1024.0), 2),
                 GCCollections = new {
-                    Gen0 = gen0,
+                    Gen0Before = gen0Before,
-                    Gen1 = gen1,
+                    Gen0After = gen0After,
-                    Gen2 = gen2
+                    Gen0Triggered = gen0After - gen0Before,
+                    Gen1Before = gen1Before,
+                    Gen1After = gen1After,
+                    Gen1Triggered = gen1After - gen1Before,
+                    Gen2Before = gen2Before,
+                    Gen2After = gen2After,
+                    Gen2Triggered = gen2After - gen2Before
                 },
                 GCMode = GCSettings.IsServerGC ? "Server" : "Workstation",
                 GCLatencyMode = GCSettings.LatencyMode.ToString()
@@ -1948,6 +1967,54 @@ public class AdminController : ControllerBase
             return BadRequest(new { error = ex.Message });
         }
     }
+
+    /// <summary>
+    /// Forces garbage collection to free up memory (emergency use only).
+    /// </summary>
+    [HttpPost("force-gc")]
+    public IActionResult ForceGarbageCollection()
+    {
+        try
+        {
+            var memoryBefore = GC.GetTotalMemory(false);
+            var processBefore = System.Diagnostics.Process.GetCurrentProcess().WorkingSet64;
+            
+            // Force full garbage collection
+            GC.Collect(2, GCCollectionMode.Forced);
+            GC.WaitForPendingFinalizers();
+            GC.Collect(2, GCCollectionMode.Forced);
+            
+            var memoryAfter = GC.GetTotalMemory(false);
+            var processAfter = System.Diagnostics.Process.GetCurrentProcess().WorkingSet64;
+            
+            return Ok(new {
+                Timestamp = DateTime.UtcNow,
+                MemoryFreedMB = Math.Round((memoryBefore - memoryAfter) / (1024.0 * 1024.0), 2),
+                ProcessMemoryFreedMB = Math.Round((processBefore - processAfter) / (1024.0 * 1024.0), 2),
+                BeforeGCMB = Math.Round(memoryBefore / (1024.0 * 1024.0), 2),
+                AfterGCMB = Math.Round(memoryAfter / (1024.0 * 1024.0), 2),
+                BeforeProcessMB = Math.Round(processBefore / (1024.0 * 1024.0), 2),
+                AfterProcessMB = Math.Round(processAfter / (1024.0 * 1024.0), 2)
+            });
+        }
+        catch (Exception ex)
+        {
+            return BadRequest(new { error = ex.Message });
+        }
+    }
+
+    /// <summary>
+    /// Helper method to trigger GC after large file operations to prevent memory leaks.
+    /// </summary>
+    private static void TriggerGCAfterLargeOperation(int sizeInBytes)
+    {
+        // Only trigger GC for files larger than 1MB to avoid performance impact
+        if (sizeInBytes > 1024 * 1024)
+        {
+            // Suggest GC collection for large objects (they go to LOH and aren't collected as frequently)
+            GC.Collect(2, GCCollectionMode.Optimized, blocking: false);
+        }
+    }
 }
 
 public class ConfigUpdateRequest

allstarr/Services/Jellyfin/JellyfinProxyService.cs

@@ -409,6 +409,7 @@ public class JellyfinProxyService
 
     /// <summary>
     /// Sends a GET request and returns raw bytes (for images, audio streams).
+    /// WARNING: This loads entire response into memory - use StreamAsync for large files!
     /// </summary>
     public async Task<(byte[] Body, string? ContentType)> GetBytesAsync(string endpoint, Dictionary<string, string>? queryParams = null)
     {
@@ -423,9 +424,35 @@ public class JellyfinProxyService
         var body = await response.Content.ReadAsByteArrayAsync();
         var contentType = response.Content.Headers.ContentType?.ToString();
 
+        // Trigger GC for large files to prevent memory leaks
+        if (body.Length > 1024 * 1024) // 1MB threshold
+        {
+            GC.Collect(2, GCCollectionMode.Optimized, blocking: false);
+        }
+
         return (body, contentType);
     }
 
+    /// <summary>
+    /// Streams content directly without loading into memory (for large files like audio).
+    /// </summary>
+    public async Task<(Stream Stream, string? ContentType, long? ContentLength)> GetStreamAsync(string endpoint, Dictionary<string, string>? queryParams = null)
+    {
+        var url = BuildUrl(endpoint, queryParams);
+        
+        using var request = new HttpRequestMessage(HttpMethod.Get, url);
+        request.Headers.Add("Authorization", GetAuthorizationHeader());
+
+        var response = await _httpClient.SendAsync(request, HttpCompletionOption.ResponseHeadersRead);
+        response.EnsureSuccessStatusCode();
+
+        var stream = await response.Content.ReadAsStreamAsync();
+        var contentType = response.Content.Headers.ContentType?.ToString();
+        var contentLength = response.Content.Headers.ContentLength;
+
+        return (stream, contentType, contentLength);
+    }
+
     /// <summary>
     /// Sends a DELETE request to the Jellyfin server.
     /// Forwards client headers for authentication passthrough.

allstarr/Services/Subsonic/SubsonicProxyService.cs

@@ -39,6 +39,12 @@ public class SubsonicProxyService
         var body = await response.Content.ReadAsByteArrayAsync();
         var contentType = response.Content.Headers.ContentType?.ToString();
         
+        // Trigger GC for large files to prevent memory leaks
+        if (body.Length > 1024 * 1024) // 1MB threshold
+        {
+            GC.Collect(2, GCCollectionMode.Optimized, blocking: false);
+        }
+        
         return (body, contentType);
     }