{"record":{"id":"d10401cb0e778fb6","repo":"SixLabors/ImageSharp","slug":"attempted-to-allocate-a-buffer-of-length-requestedlength","errorCode":null,"errorMessage":"Attempted to allocate a buffer of length={requestedLength} that would increase the accumulative allocation size to {totalLength}, exceeding the limit {limit}.","messagePattern":"Attempted to allocate a buffer of length=(.+?) that would increase the accumulative allocation size to (.+?), exceeding the limit (.+?)\\.","errorType":"exception","errorClass":"InvalidMemoryOperationException","httpStatus":null,"severity":"error","filePath":"src/ImageSharp/Memory/InvalidMemoryOperationException.cs","lineNumber":45,"sourceCode":"    {\n    }\n\n    [DoesNotReturn]\n    internal static void ThrowNegativeAllocationException(long length) =>\n        throw new InvalidMemoryOperationException($\"Attempted to allocate a buffer of negative length={length}.\");\n\n    [DoesNotReturn]\n    internal static void ThrowInvalidAlignmentException(long alignment) =>\n        throw new InvalidMemoryOperationException(\n                $\"The buffer capacity of the provided MemoryAllocator is insufficient for the requested buffer alignment: {alignment}.\");\n\n    [DoesNotReturn]\n    internal static void ThrowAllocationOverLimitException(ulong length, long limit) =>\n            throw new InvalidMemoryOperationException($\"Attempted to allocate a buffer of length={length} that exceeded the limit {limit}.\");\n\n    [DoesNotReturn]\n    internal static void ThrowAccumulativeAllocationOverLimitException(long requestedLength, long totalLength, long limit) =>\n            throw new InvalidMemoryOperationException(\n                $\"Attempted to allocate a buffer of length={requestedLength} that would increase the accumulative allocation size to {totalLength}, exceeding the limit {limit}.\");\n}\n","sourceCodeStart":27,"sourceCodeEnd":48,"githubUrl":"https://github.com/SixLabors/ImageSharp/blob/59ce6af6fc29027cda277ef62d4d1694a8acce91/src/ImageSharp/Memory/InvalidMemoryOperationException.cs#L27-L48","documentation":"Like the single-buffer limit throw, this fires when a requested allocation is over the accumulative limit: granting it would push the allocator's TOTAL outstanding allocation size above the configured cap. It protects against cumulative memory exhaustion across many buffers, e.g. during large multi-buffer decodes.","triggerScenarios":"Any allocation request where (currently tracked total + requestedLength) > AllocationLimit — commonly while decoding large images whose decoders allocate several big buffers, or under sustained concurrent image processing sharing one limited allocator.","commonSituations":"Server workloads processing many large images concurrently under one memory-limited Configuration; large panoramas/mosaics whose decode needs multiple buffers that together exceed the cap; limits set for one workload then applied to a heavier one.","solutions":["Increase the accumulative AllocationLimit in the allocator configuration to cover the real concurrent working set.","Reduce concurrency (process images sequentially or with fewer parallel tasks) so outstanding allocations stay under the limit.","Dispose images/buffers promptly (using statements) so returned memory lowers the accumulative total before new requests."],"exampleFix":"// before\n// limit 256MB, concurrency 32 -> total requests exceed limit\nParallel.ForEach(files, f => using-image-load(f));\n// after\n// raise limit and/or limit parallelism\nParallel.ForEach(files, new ParallelOptions { MaxDegreeOfParallelism = 8 }, f => using-image-load(f));","handlingStrategy":"try-catch","validationCode":null,"typeGuard":null,"tryCatchPattern":"try { using var image = Image.Load(config, stream); }\ncatch (InvalidMemoryOperationException ex) when (ex.Message.Contains(\"accumulative\"))\n{ /* reduce concurrency or raise the accumulative limit and retry */ }","preventionTips":["Bound parallel image-processing concurrency to what the accumulative limit can absorb.","Dispose IMemoryOwner buffers and images deterministically with using/await using.","Set the accumulative AllocationLimit from measured peak concurrent working set, not guesses."],"tags":["memory","allocation-limit","concurrency","configuration"],"backgroundTag":"file-size-limit-exceeded","analyzedSha":"59ce6af6fc29027cda277ef62d4d1694a8acce91","analyzedAt":"2026-09-13T18:34:59.331Z","contentChangedAt":"2026-09-13T18:34:59.331Z","schemaVersion":2},"datasetVersion":"2026-09-16T04:17:20.429Z"}