My first thought reading this was to answer suggesting some while {...}, emitting some form of progress information -- a scale, or a repeating "Please wait..." output, ...

This would have served 2 purposes; 1) overcome "timeout thresholds"; both the web server, as well as the web client (browser). 2) provide feedback to the user; the threshold of users attention span has greatly diminished, since the dawn of the internet.

All the best.

--Chris