silverstripe-staticpublishqueue | This module allows you to build static HTML caches of every page (for increased security and perform | Caching library

My company uses SilverStripe v3.1.21, along with the Subsite module to display and administer a number of clients' websites that sell products. This results in close to 200 subsites and a page count in the tens of thousands. The websites are very slow to load and tools such as Google's PageSpeed tell us page speeds are poor. We've already done step like combining and minimising the JS and compressing resources such as imaging, which gave some improvements, however the pages remain slow. The system was handed to us in this state and further hardware upgrades are not on the table as an option, nor are gaining additional resources for redevelopment.

We've taken a look at the static publish module (https://github.com/silverstripe/silverstripe-staticpublisher) and found that when we generating static pages the pages become fast and get a good score on the various tools, however the process to regenerate all of these pages takes over 14 hours, which is unacceptable given these products are updated from an external source daily. We also find that the regeneration process is a memory hog, as the module builds all of the pages in memory before dumping to file, causing the process to crash. We've had to alter the process to go subsite-by-subsite just to make it run.

We then took a look at the static publishing queue module (https://github.com/silverstripe/silverstripe-staticpublishqueue), which seemed to address our issues by having it queue pages as needed for regeneration, making it much more responsive to changes. However, the module seems to be very buggy and often crashes when generating pages.

Has anyone had experience using these modules (or similar) with larger sites and may be able to provide any pointers or ideas on how to implement static publishing successfully?