Hello I am working on a work bench that has a 6 core cpu and 64 gb of ram. I was wondering if there is any way that I could set up my mantra render so that it only uses 1 core per frame and renders multiple frames at a time.

Multithreading the render doesnt end up using nearly all of the ram which I would like to take advantage of.

Theoretically you can use the command line to launch different render sessions, that use just 1 processor but I don't how much you can gain in final render time. Have you tried to do0 some test?

on Mantra ROP/Main tab
click on the arrow next to Command parm and chose Use One CPU
which will fill in the command for you

then it's up to you to run more frame at once (in parallel) with some script or something

Running multiple mantras vs. a single threaded mantra will also render your CPU's L3 cache nearly useless, as you have a bunch of mantras with different memory spaces contending for the L3. A single threaded mantra will have far more cache hits, decreasing memory bandwidth/latency. Just something to consider if you're finding performance is down a bit. You might want to try 4 mantras running 3 threads (for a 12-thread CPU) or various combinations like that, to see if that improves things overall.

To do it automatically you'll have to set up Hqueue with 6 “nodes” on your one machine, then tell Mantra (as described above) to use 1 core. No, I don't know how to do this

Definitely test, to see what is most efficient. Mantra is quite well threaded, though not completely, so sometimes you can just throw all cores at one frame and it's very close to the same as doing 6x frames on 1 core each.

Other times, there may be a higher percentage of non-threaded CPU time (loading geometry, for example) where running 6x frames at the same time buys you more.

In practice, each scene is different and you need to test.

Great thanks ill let you know how it goes.

I am exploring this now myself, esp with the advent of Ryzen 7 - ,multi core machines
and id like to know of any changes - technical advice. if sesi or any users have any experience or tips with multiple frame rendering on one machine.

You probably won't see any advantage nowadays in raytrace nor PBR mode (due to its almost perfect threading). Micropolygon may run faster (it definitely used to).