flycheck: add option to set lower priority

[ShadowJonathan]

Often enough i have large projects where cargo check takes a long time, I switch away to do some other things while it churns away, but often enough my PC is slowed down to a crawl due to cargo being CPU-heavy.

I'd like to have the ability to have rust-analyzer put cargo on a higher nice value (lower priority), so it doesn't affect a lot of other things on my PC

[lnicola]

After the project is loaded, the only cargo command is cargo check, which you can override. If you're on Linux, you can put nice in there.

[ShadowJonathan]

How exactly? I looked at the config page, but i didn't see this.

[lnicola]

    "rust-analyzer.checkOnSave.overrideCommand": [
        "nice",
        "-n2",
        "cargo",
        "check",
        "--all-targets",
        "--message-format=json"
    ]

[ShadowJonathan]

ah, thanks, then this issue can be closed

[lnicola]

It's a reasonable feature request, but we generally avoid platform-specific code, so I'm not sure we'd want to implement this across the platforms where there's an API for it. Windows has it, but on Unix I think we'd have to call nice in pre_exec.

[ShadowJonathan]

maybe something like low_priority: true?