I have a program which summarises large Exel files (up to 150mb) in batches from anywhere 5 to 150 files. The major bottleneck for this is the time it takes to load in each file, so I am considering incorporating some multi-threading to start this whilst the user is screwing around in the GUI choosing summarisation options. My question is, would it be better to load several files at the same time or several files in succession? One of the major bottlenecking issues is that several users use network drives to store their files so is it worth loading a few at the same time, or is that pointless seeing only so much bandwidth is available (at the moment loading one file in at a time uses about 80% of the bandwidth). I am aware of the memory issues that could arise with this approach and will only grab the parts of the file I need and put them into an array before closing the file. In addition I would only keep a few file arrays in memory at any time.

Any suggestions would be great.