I am currently subscribed to three projects. My computer is running only about 2-3 hours a day, and even throttled to avoid the fan going though the roof. With this limited time available, I do not want to download several tasks of different projects, only to see them expire.

Is there an option for BOINC to download one task, run it and then fetch a new one? I do not need nor want to have several tasks in the cache, as BOINC could easily ask for and download it at the time one task is finished. Am I right to assume all scheduling decisions by BOINC rely on the basis the computer is running all the time?

Thanks for your input and help!
Best regards,
Frank

P.S. I already tried setting fetch-minimal-work in the config file. For whatever reason, BOINC sometimes refuses to download new work, even if no task is being processed then.

One thing that you can do is set the percentage of cpus on your computer to a value that equates to only one processor.
Do this for each of your projects.

You should then get one task, and then "your cache will be full", so that it doesn't ask for anything else from any project.

I haven't tried this, but I suppose you could set the resource share for all projects to 0. Additionally, you could set all projects to No New Tasks. Then, whenever you want to run Boinc, you could select the project you want to run and Allow New Tasks. With the resource share at 0 it should only download enough tasks for the processors you have active. When you don't want that project to download any further tasks you can set it back to No New Tasks. If you don't want all CPU cores to crunch tasks, follow Les' advice and reduce the percentage.

I know this seems to make running Boinc quite a bit more manual than automatic, but I'm guessing you are okay with that.

I haven't tried this, but I suppose you could set the resource share for all projects to 0. Additionally, you could set all projects to No New Tasks. Then, whenever you want to run Boinc, you could select the project you want to run and Allow New Tasks. With the resource share at 0 it should only download enough tasks for the processors you have active. When you don't want that project to download any further tasks you can set it back to No New Tasks. If you don't want all CPU cores to crunch tasks, follow Les' advice and reduce the percentage.

I know this seems to make running Boinc quite a bit more manual than automatic, but I'm guessing you are okay with that.

This works. I do this to have a backup project in case the project I am running runs out of work. With 0 resource share the task count = CPU count. No tasks will be waiting to run.

I haven't tried this, but I suppose you could set the resource share for all projects to 0. Additionally, you could set all projects to No New Tasks. Then, whenever you want to run Boinc, you could select the project you want to run and Allow New Tasks. With the resource share at 0 it should only download enough tasks for the processors you have active. When you don't want that project to download any further tasks you can set it back to No New Tasks. If you don't want all CPU cores to crunch tasks, follow Les' advice and reduce the percentage.

I know this seems to make running Boinc quite a bit more manual than automatic, but I'm guessing you are okay with that.

This works. I do this to have a backup project in case the project I am running runs out of work. With 0 resource share the task count = CPU count. No tasks will be waiting to run.

I have backup projects with a resource share of 0 as well. To clarify, I am not sure what happens when ALL projects in Boinc manager have a resource share of 0.

P.S. I already tried setting fetch-minimal-work in the config file. For whatever reason, BOINC sometimes refuses to download new work, even if no task is being processed then.

Because that's the function of fetch_minimal_work: it downloads one task per device (CPU, GPU) and when those are done it won't fetch new work. This is a debug function for the client, normally used in combination with --exit_when_idle where it will exit the client when all tasks have been done, uploaded and reported.

Use the resource share is 0 (zero) option the others have pointed out. This will always download just one task per given hardware device (CPU core, GPU). This option has to be set at the projects' Project Preferences or if you use an account manager, there. It cannot be set via BOINC Manager.

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