File upload from azure app service to file share is very slow

So I have this setup:

• a blazor web app project
• .net 8
• hostested in Azure app service with the Standard S1 tier.
• a storage account from where I use file share to maintain documents from the app.

What I am trying to do?

I am trying to upload files from the blazor app to the file share.(I make a transition from web forms to blazor and file shares is already there so I cannot use something else).

Problem and what I tried so far

When I upload files from the application hosted in azure, the upload takes over 70 seconds for a 15MB pdf. This should be done faster as the user will have a problem with this.What could be the problem?

So far I tried multiple solution(for each solution the upload from my local machine works fast as I would like to be, so from this I suppose that the problem comes from azure app service somehow).

For each of the solutions presented below I also tried different app service plans. Standard S2 and all the premiums ones.

Solution 1:I tried to mount the file share in the app service. It uploads but it takes very long time.

Solutions 2:I tried using Azure.Storage.Files.Shares to upload directly to the file

 using var fileStream = fileUpload.File.OpenReadStream(long.MaxValue); // Limit max size to handle larger files if needed      long fileSize = fileStream.Length;      const int chunkSize = 4 * 1024 * 1024; // 4MB per chunk      await fileClient.CreateAsync(fileSize);      byte[] buffer = new byte[chunkSize];        long offset = 0;        // Store the tasks for parallel execution        var uploadTasks = new List<Task>();        while (offset < fileSize)        {            int bytesRead = await fileStream.ReadAsync(buffer, 0, chunkSize);            if (bytesRead == 0)            {                break;            }            // Copy the data to avoid threading issues            var chunkData = new byte[bytesRead];            Array.Copy(buffer, 0, chunkData, 0, bytesRead);            long currentOffset = offset;            // Create and store the upload task            var task = Task.Run(async () =>            {                using (var memoryStream = new MemoryStream(chunkData))                {                    await fileClient.UploadRangeAsync(new HttpRange(currentOffset, bytesRead), memoryStream);                }                //progressCallback(currentOffset + bytesRead, fileSize);            });            uploadTasks.Add(task); // Add the task to the list            offset += bytesRead; // Move the offset forward        }        // Wait for all upload tasks to finish        await Task.WhenAll(uploadTasks);

Solution 3: I tried Microsoft.Azure.Storage.DataMovement which I read that this package is desined for blobs and for large files. I managed to point it to my file share and upload file but the same problem.

 CloudFile fileReference = uploadFileLocal.GetFileReference(fileUpload.File.Name.Trim()) var transferContext = new SingleTransferContext {     ProgressHandler = new Progress<TransferStatus>(progress =>     {         progressCallback(progress.BytesTransferred, fileUpload.File.Size);     }) }; // Perform the upload using DMLib // await TransferManager.UploadAsync(tempFilePath, fileReference, null, transferContext); using (var stream = fileUpload.File.OpenReadStream(104857600)) {     // Perform the upload using DMLib     await TransferManager.UploadAsync(stream, fileReference, null, transferContext); }

I also tried to save the file to the disk first and there I noticed that the disk upload took over 70 seconds and after the upload to file share took 2 seconds.. When uploading I would have given the file path await

TransferManager.UploadAsync(tempFilePath, fileReference, null, transferContext);

Nothing is working. What can I do?