Is there a command for the config file where I can ask it to only run on 1 of 2 GPUs? That way I can save my other GPU for a different piece of software?

https://boinc.berkeley.edu/wiki/Client_configuration

U can use "exclude_gpu" in the cc_config.xml file

---

Suppose there are more than 1 GPUs, how do you determine the

<device_num>

of the GPUs you want to exclude?

<exclude_gpu>
   <url>project_URL</url>
   [<device_num>N</device_num>]
   [<type>NVIDIA|ATI|intel_gpu</type>]
   [<app>appname</app>]
</exclude_gpu>

because

 If <device_num> is not specified, exclude all GPUs of the given type.

Suppose there are more than 1 GPUs, how do you determine the

<device_num>

of the GPUs you want to exclude?

Look at the startup lines in the BOINC Event Log. Each device is identified by name and number.

@Richard

By using the "exclude_gpu" option in cc_config files in respective project folders, would you be able to run different projects on specific GPUs concurrently?  For example, Project A would run on <device_num> 2, and Project B would run on <device_num> 1.

Well, something like that - it's possible, but don't do it like that.

cc_config.xml is one file - singular. It's a BOINC file, and it belongs in the root of the BOINCdata folder tree, wherever you have chosen to put that on your personal system.

Tip - the best thing to do is to open the Event Log options dialog (Ctrl+Shift+F), make a trivial change or two (<cpu_sched> and <sched_op_debug> are useful, without being too verbose), and 'OK' the changes. That will write out a complete cc_config.xml file with all allowed tags and current values: it's a really helpful framework to build your customisations on.

Then, open Client Configuration Options and build your GPU exclusions according to the example given. In your example, each project will need a separate <exclude_gpu> block of its own. Remember that [square brackets] in computer manuals are used to denote optional sections - either delete the brackets to make the directive active, or leave out the line completely if you don't want it.

<exclude_gpu> is one of the cases where you need a complete client restart to activate it - 'Read config files' isn't enough. You may encounter some unexpected changes in work fetch and scheduling after setting a GPU exclusion - I've found one significant (replicated and reported) bug in there, but nothing's been done about it yet.

Well, something like that - it's possible, but don't do it like that.

cc_config.xml is one file - singular. It's a BOINC file, and it belongs in the root of the BOINCdata folder tree, wherever you have chosen to put that on your personal system.

I thought it covered all projects on a rig, I was a tad confused.  I had forgotten that I had created a cc_config.xml file months ago.

Then, open Client Configuration Options and build your GPU exclusions according to the example given. In your example, each project will need a separate <exclude_gpu> block of its own.

It would be easier having multiple <exclude_gpu> blocks in one place.
Immense thanks.