SFTP download is slow

[Sravdar]

Hello. I do host sftp server on same computer where i do this test. Using windows machine, "sftpgo" for the sftp server.

When i try to download files via following code i get around max 1MB/s speed. When using filezilla i can get about 200 MB/s. Is there anyway to write this code in more optimized way? I am open for ideas here.

var remoteFileConnection = await sftp.open(file.filename, mode: SftpFileOpenMode.read);
var writeFile = File(p.join(pathSftpCache, file.filename));
if(writeFile.existsSync()) {
  writeFile.deleteSync();
}
writeFile.createSync(recursive: true);
var writeStream = writeFile.openWrite();
var readStream = remoteFileConnection.read();

await for (final chunk in readStream) {
  copiedBytes += chunk.length;
  writeStream.add(chunk);
  onProgress(copiedBytes / totalDownloadSize);
}

dartssh2: ^2.11.0

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