Is it possible to create TDocStd_Document instance from an existing file.xbf?

I want somehow to accelerate a model downloading. The slowest operation is transferring data from a step file to the TDocStd_Document ( stepReader.Perform(pathToStepFile, document) ) – for 20mb model it takes 10 seconds. I am curious about transferring data only once and then just use previously saved TDocStd_Document file. I would be glad to hear any suggestions how to speed up the process of creating a document from a file, or other best practices about displaying the model with all its nested sub shapes.