Testing and Optimizing Transfer Performance

To verify that your system's FASP transfer is reaching the target rate and can use the maximum bandwidth capacity, prepare a client machine to connect to this server. For these tests, you can transfer an existing file or file set, or you can transfer uninitialized data in place of a source file, which you can have destroyed at the destination, eliminating the need to read from or write to disk and saving disk space.

To send random data in place of a source file, run the following command:

# ascp --mode=send --user=username --host=host_ip_address faux:///fname?fsize target_path

where fname is the name assigned to the file on the destination and fsize is the number of bytes to send. fsize can be set with modifiers (k/K, m/M, g/G, t/T, p/P, or e/E) up to 9 EB.

To send a file but not save the results to disk at the destination, run the following command:

# ascp --mode=send --user=username --host=host_ip_address source_file1 faux://

To send random data and not save the results to disk, run the following command:

# ascp --mode=send --user=username --host=host_ip_address faux:///fname?fsize faux://

For usage examples, see Ascp General Examples. Once you start a transfer from the command line, you can monitor it from the GUI.

  1. Start a transfer with Fair transfer policy and compare the transfer rate to the target rate.
    On the client machine, open the user interface and start a transfer (either from the GUI or command line). Click Details to open the Transfer Monitor.

    To leave more network resources for other high-priority traffic, use the Fair policy and adjust the target rate and minimum rate by sliding the arrows or entering values.

  2. Test the maximum bandwidth.
    Note: This test will typically occupy a majority of the network's bandwidth. Aspera recommends performing it on a dedicated file transfer line or during a time of very low network activity.

    Use Fixed policy for the maximum transfer speed. Start with a lower transfer rate and increase gradually toward the network bandwidth.

To improve the transfer speed, you may also upgrade the related hardware components:

Component Description
Hard disk The I/O throughput, the disk bus architecture (e.g. RAID, IDE, SCSI, ATA, and Fiber Channel).
Network I/O The interface card, the internal bus of the computer.
CPU Overall CPU performance affects the transfer, especially when encryption is enabled.