# Migrating a large forum **URL:** https://meta.discourse.org/t/migrating-a-large-forum/37838 **Category:** Support **Created:** [January 12, 2016, 3:59pm UTC](https://meta.discourse.org/t/migrating-a-large-forum/37838 "2016-01-12T15:59:25Z") **Posts on this page:** 1 **Showing post:** 3
### Author: ![DeanMarkTaylor](https://sea3.discourse-cdn.com/meta/user_avatar/meta.discourse.org/deanmarktaylor/32/102462_2.png) [@DeanMarkTaylor](https://meta.discourse.org/u/DeanMarkTaylor) #### Post date: [January 12, 2016, 5:31pm UTC](https://meta.discourse.org/t/migrating-a-large-forum/37838/3 "2016-01-12T17:31:22Z")
This post I made in the discussion from [phpBB 3 Importer (old)](https://meta.discourse.org/t/phpbb-3-importer-old/17397/75) might be of interest to you: > [@phpBB 3 Importer (old)](https://meta.discourse.org/t/phpbb-3-importer-old/17397/75): > > My largest final import output 424.7K posts over 39.6K topics and 10.2K users. > > Creating the Digital Ocean instance at 2GB with a 2GB swap and then bumping it to a 16GB instance for the import only required 3 restarts. > > I monitored the progress (in a spreadsheet) and when the post `imports per second decreased` and started to tail off - I just Ctrl+C the import and then started it again. > The import process slows because of the memory hole. > > All the while I had at least 25 sidekiq’s running - basically enough to keep the CPU at ~80% clearing the backlog of stuff at the same time as the import. Yes, this was an older version of in the import script but might still be relevant. It turns out the import was more like just over 750K posts and 150K topics including private messages. The sidekiq’s execute background tasks created by each imported post and it’s always worth a little look in `/sidekiq` to see if you have a backlog. That’s the reason I mention “at least 25 sidekiq’s running” to keep that those tasks down. My import ran for well over 36 hours on a 64GB Memory, 20 Core Processor machine which I ended up using. --- _[View the full topic](https://meta.discourse.org/t/migrating-a-large-forum/37838)._