Blackmagic Forum

Page 4007 of the v19 manual discusses this.
It would imply that collaborative render cache is more than just my wishful thinking or imagination.

Exhaustively trawling both here and the Web , has yielded zero success, with the majority claiming for versions pre 19, a render cache can not be shared and is unique to a specific machine. Others have gone as far as to say it's by design so that each user can tailor they're render settings based on machine speed etc.

So, if that's the case, can anyone explain the following?

"Each collaborator on a project will have the exact same render cache format settings automatically
configured across all machines. If you are collaborating across operating systems (Mac, Windows,
Linux), it is important that the Render Cache Format is set to a codec that is supported by all platforms."

Grateful for any constructive responses, thanks.

We've tried specifying render cache paths to network shares both in the preferences and in the project settings. We've also tried only setting one of these and not the other.

Just giving this a bump in case any facilities using PCs might be able to help?

Via BM support we've been assured that render caches should share, with all users setting their media storage preference to the same location (we've done this down to matching the exact drive letter etc), or also by using path mapping at a project level setting. Basically, the advice is to make sure everything is set identically across all systems, which we've done, in a collaborative project.

Anecdotally, I've been told by a MAC based facility here in London that this works as expected and is an essential part of their day to day workflow process, moving jobs between grades, onlines and tech for delivery.

At the moment BM take about a week to respond and it's only first level of support without any input from engineering. I'd gladly pay for engineering support to get this remedied, baring in mind we're Resolve Studio and we need this to work.

Can anyone with any experience help?

Thanks.

We've succeeded in achieving our goal of sharing a render cache.

Render caches can persist (assuming each user set their media drive to the same location and drive letter on a PC). However the project must not be shared / set to "multi user collaboration".

In our case simultaneous collaboration is not the goal, we simply want to pass a project between different users on different machines in different edit suites. Keeping the project effectively as single user (despite it being located on the project server and available to all) is counterintuitive, but it's key to being able to maintain an existing render cache and avoid lengthy rebuilds and doubling-up on storage.

The process is successful in a single user / none collaborative project. A render cache will persist between users so long as it's not a shared project. Of course, only one user can access the project at a time, but that works for us.

Hi, appreciate you posting the follow up!!

I'm trying to figure out the advantages to setting a project to single user / multi user. It seems this is one of them - having a shared cache.

Have you found any other advantages?

At our facility a shared persistent cache is far more valuable than a shared project and simultaneous collaboration.

I could see collaboration as very useful on a fast turnaround project with a tight TX, at which point being able to online, grade, witness protect / blur at the same time would justify multiple individual (non shared), duplicate render caches.

One disadvantage is that it pretty much dictates each episode in its own unique project. Depending on workflow, this might be an annoyance.

ogriff79 wrote:At our facility a shared persistent cache is far more valuable than a shared project and simultaneous collaboration.

I could see collaboration as very useful on a fast turnaround project with a tight TX, at which point being able to online, grade, witness protect / blur at the same time would justify multiple individual (non shared), duplicate render caches.

One disadvantage is that it pretty much dictates each episode in its own unique project. Depending on workflow, this might be an annoyance.

I assume the shared cache is with a NAS system? I wonder if this would work for remote users?
And are you mostly using it to cache vfx shots and the like?

Yes, dedicated Video shared storage systems, 10gb over Fibre. We have Avid Nexis and Editshare servers.

The biggest render burden tends to be video Noise Reduction, but any heavy temporal effects are best node cached, which really speed things up after that.

We also deliver HD masters of heavily composited studio shoots, blending as live with complex 3D VFX, using native blend modes (usually 'screen'), keying through black (rather than traditional chromakey). Rushes and VFX tend to originate UHD, and there's a lot of rescaling for virtual jib and rostrum moves. Add a grade plus NR into the mix and a fast render cache is essential.

Up until now we've had to rebuild (duplicate) caches.

ogriff79 wrote:Yes, dedicated Video shared storage systems, 10gb over Fibre. We have Avid Nexis and Editshare servers.

The biggest render burden tends to be video Noise Reduction, but any heavy temporal effects are best node cached, which really speed things up after that.

We also deliver HD masters of heavily composited studio shoots, blending as live with complex 3D VFX, using native blend modes (usually 'screen'), keying through black (rather than traditional chromakey). Rushes and VFX tend to originate UHD, and there's a lot of rescaling for virtual jib and rostrum moves. Add a grade plus NR into the mix and a fast render cache is essential.

Up until now we've had to rebuild (duplicate) caches.

I see. Thanks for the detailed response.