I think the first thing to identify would be what is eating up so much space in the NCrunch workspace. NCrunch can and will duplicate your projects inside the workspace, though not normally more than would be required to run things in parallel - so using more than 6GB on a 250MB solution seems quite extreme.

How much space is used by your nuget packages? NCrunch will copy/duplicate these to EVERY workspace, so if you have a large number of projects using many nuget references, this could get very hungry. Also, do you have any large resource files that are shared between projects that you've identified by using the 'Additional files to include' setting?

That does sound like it would likely be the source of most of the disk consumption. How many projects do you have in your solution?

Ok - it's almost certainly the duplication of the nuget resources then. 24 * 120 = 2880MB and then this will be duplicated again for some of the projects you're actively working in.

For the time being, I think it's a safe assumption that the layout of this solution won't fit on a RAM drive. I'll make a note in my backlog to have a think about how NCrunch may be able to handle this better. Thanks for reporting this problem!

For anyone interested, the recently released v1.39b contains a fix that should greatly reduce the disk consumption of solutions that are using Nuget.

Are there any obvious indications around what is taking up all the space? Can you give me a rough count of the number of project workspaces that NCrunch has created on your RAM drive? (these are basically just directories with numbered names nested underneath a directory with the same name as the ID of the devenv.exe process).