If you are serving the file directly to a web browser via an API, avoid saving to a local disk first. Use OpenStreamWithResponseAsync to stream the S3 content directly to the HTTP response.
For objects not uploaded as multipart, set MultipartDownloadType to RANGE . This allows the SDK to use HTTP byte ranges to download parts in parallel. download large file from s3 c#
Large downloads can exceed standard HTTP timeouts. Increase the timeout settings on your AmazonS3Client or use the TransferUtility , which handles retries and connection management internally. If you are serving the file directly to
public async Task GetLargeFileStreamAsync(string bucketName, string key) { var transferUtility = new TransferUtility(new AmazonS3Client()); var streamResponse = await transferUtility.OpenStreamWithResponseAsync( new TransferUtilityOpenStreamRequest { BucketName = bucketName, Key = key, MaxInMemoryParts = 5, // Limit memory consumption MultipartDownloadType = MultipartDownloadType.PART }); return streamResponse.ResponseStream; } Use code with caution. 4. Key Performance Strategies This allows the SDK to use HTTP byte