I see, my projects are such that if i run out of gpu memory it means i need a new graphics card not a poolsize rethink 
In all seriousness i was getting odd effects. I would increase pool size to 4000 after looking at relevant threads on this site, stats were showing a lot less than the limits but i was still getting problems so i turned it off. I launched the culprit project with texture streaming turned off and didn’t notice any long loading times (3 rooms few items of furniture) only have a gtx 960 4gb. Maybe it’s good to keep in mind what you pointed out as my scenes increase in size .
Cheers