Delta File Transfer (DFT)

ProjectWise includes file transfer technology that can significantly reduce the amount of time required to check out and check in ProjectWise documents. This technology, referred to as Delta File Transfer (DFT), optimizes file transfers by only transferring those parts of a file that have been modified. Because the performance of this feature is greatly dependent on an organization's network infrastructure, a benchmark tool has been provided with the ProjectWise Administrator installer that will allow the end-user to perform various file transfer tests to determine how much of a benefit DFT will provide.

If you are running this test against a new datasource, DFT is on by default. If you are running this test against a datasource that has been upgraded from a pre-V8i version, you must first enable the Delta File Transfer datasource setting.

Note: You do not need administrator privileges to run the Delta File Transfer Benchmark tool, however you will need to run the tool as an administrator if you want the tool to collect performance counter data.

Note: DFT technology is designed to provide better file transfer performance over low-bandwidth/high-latency network links. It is possible that negative performance results may occur when using DFT over high-speed LAN links. This is a known shortcoming of any kind of differential file transfer algorithm.

Note: As a security measure, ProjectWise limits the amount of time that may pass between the start of a checkout command and the start of the actual file transfer from the storage area to the client. With the introduction of DFT, ProjectWise must now spend additional time calculating the deltas (differences) between the two files prior to the actual file transfer operation itself. In some cases, for exceptionally large files, the time required to calculate the differences may exceed the checkout/file transfer time limit. In this case, the value of the FileAccessTokenLifetime setting in the dmskrnl.cfg file may need to be increased to deal with these scenarios. A service restart is not needed after this value is modified; the new time limit will take effect immediately.

After the test completes you have the option of saving the results for later review. There is also an option to submit your results to Bentley for analysis. We ask that you do so, so that we can tune the DFT feature to be more performant on our customer's real-world systems.

Note: No personally identifiable information (other than your email address) or information about your organization's internal infrastructure is transmitted to Bentley. You will be given a change to review the full and complete text of the email before it is submitted to Bentley, and you will be given an opportunity to decline to send the email.

Enable the Delta File Transfer datasource setting

Open ProjectWise Administrator and log in to the datasource you will be using for the benchmark.
Right-click your datasource and select Properties.
On the Datasource Properties dialog, select the Settings tab.
Expand the Network category and turn on Enable Delta File Transfer.

Run the Delta File Transfer Benchmark tool

In Windows Explorer or in a command prompt, navigate to C:\Program Files (x86)\Bentley\ProjectWise\bin.
Run the DFTBMWIZ.EXE application. A wizard opens to guide you through the process of running the application.

The application can be run in two modes, auto or manual.

The auto test will generate three files (small, medium, and large) in your workstation's temporary directory, and will use those files to gauge the performance of the DFT technology. The application will import these documents into a test folder in your datasource, check them out, make a predefined set of changes to the file data, and check the modified files back in. The application will then report the efficiency of the DFT operation, based on the predefined, scripted changes.

The manual test requires that you provide a set of files for the test. Two copies of each file must be provided: a baseline copy of the file, and a copy that contains a known set of changes.

This is so that you can gauge the performance of the DFT technology based on set of changes that you have personal control over.

The before and after copies of the file or files should be placed in separate directories.

After the test completes, various reports can be viewed to show the file transfer performance increase.