Blackmagic Forum

For the last couple of days I've been trying to export a project. I'm exporting to an external SSD. My Cache folder is also set to an external SSD, as is my database. Each time I try to export the entire project (one 16 minute clip) it gets about halfway and then Resolve crashes. I can see why it crashes but I'm not sure what is causing this behavior.

As the export is taking place the internal hard drive begins filling up, quickly. I have screen recordings I can share. I started out with nearly 900GB of free space but after an hour or two I'm down to 41MB! When looking at the Macintosh HD in Finder it certainly doesn't look like I am full, although it indicates this at the bottom of the window and in the get info panel.

When all of my rendering is pointed to external sources, at least everything that I can think of this doesn't make sense. The file should be roughly 12GB when exported. I have plenty of space on the external SSD. I can export smaller partial clips but the Macintosh hard drive does begin filling up from these exports as well, just not completely. 

And strangely enough even after Resolve has quit I still am loosing SSD space, just not nearly as quickly. In the time to write this it is now down to 34MB. Restarting the computers seems to clear everything up.
I did just update to Big Sur.

iMac Pro 8-Core 64GB RAM and Radeon Pro Vega 64 16GB
I've been a Final Cut user for almost 20 years. I'm certainly not as familiar with all the ins and outs of Resolve, but I had not encountered this issue until recently.
Thanks Phil

Try, turn off all your cache.
Empty all the cache folders.
Cold reboot the computer.
See what that does.

I've Turned off all Cache rendering, Playback>Render Cache>None. Playback>Fusion Memory Cache>Off, I've emptied all cache, Playback>Delete Render Cache>All. I Shutdown the computer, unplugged it waited ~15 seconds and rebooted.
My Render Cache folder is on an external Samsung SSD.
I've run other projects with no problems from this database and others.
I've tried copying this project into a new database (I think I did this correctly - still learning)

A new project in the same database = no problem
A new timeline in the same project = same problem but slower fill up
A new timeline with the original material copied and pasted = same quick fill up.

I'm totally stumped.

Figured it out with the help of my IT dept.

I could see the hard drive usage going up but I could not see where it was filling up. A deep dive led us to Macintosh HD > Private >Var >Folders > 8b >T (and a couple of similar trails) Here I found a folder labeled DiskCache folders and inside these were folders labeled Fu_Merge6_28-May-21_08-50-39_46 and inside that was a DiskCachexxx.raw file.
This led us to Fusion where I had two nodes, a Channel Booleans and a Merge that were set to Render to Cache (I thought I was doing it correctly but maybe not. The Channel Boolenans was feeding into the Merge Node's mask input. After unchecking Render to Cache. I was finally able to export correctly.

So, did I do something wrong or is this a bug?