error 504 Gateway timeout due to high number of links between item

I am using Codebeamer Release 3.1 and Datecode3.1.0.0 We have a performance problem in a specific project due to high numbers of link between items with another project and a little complexity for computed fields. This cause the error 504 Gateway timeout and it becomes impossible to edit/create items. We already have increased the time to reach timeout up to 300 seconds. We would like to reduce the loading time of the items, not increasing more time. It's a blocking point and we must improve the performance as soon as possible. Here are the errors that I faced HTTP Error 504: Gateway Timeout