Warning that occur when executing `cargo run`

When I run cargo run on the dev container created by vscode, I get the following warning.
If you know the cause, please let me know.

<jemalloc>: MADV_DONTNEED does not work (memset will be used instead)
<jemalloc>: (This is the expected behaviour if you are running under QEMU)

The following is information on the development environment

rustc 1.64.0 (a55dd71d5 2022-09-19)
cargo 1.64.0 (387270bc7 2022-09-16)
rustup 1.25.1 (bb60b1e89 2022-07-12)
info: This is the version for the rustup toolchain manager, not the rustc compiler.
info: The currently active `rustc` version is `rustc 1.64.0 (a55dd71d5 2022-09-19)`

$ rustup show
Default host: x86_64-unknown-linux-gnu
rustup home:  /usr/local/rustup
1.64.0-x86_64-unknown-linux-gnu (default)
rustc 1.64.0 (a55dd71d5 2022-09-19)

What does uname -a show inside the container? And what kind of container are you running? Docker on linux, docker on Windows or macOS, WSL1, WSL2, ...

Thank you for your reply!

uname -a

Linux 48c7acd60203 5.10.76-linuxkit #1 SMP PREEMPT Mon Nov 8 11:22:26 UTC 2021 x86_64 GNU/Linux

My container is docker on macOS.

The warning seems to be expected when using Docker on macOS. I think it is something unimplemented on their end. In any case it shouldn't cause any issues than slightly lower performance.

1 Like

Thank you very much!
Let me know if you know where I can find something written about it :slight_smile: