Re: Rust build huge memory consumption

Hi,

On Wed, Oct 25, 2023 at 08:38:54AM +0200, Xavier Humbert wrote:
>Hi,
>
>When building rust, all memory is eaten, leading to OOM killing almost 
>everything, eventually failing, and leading to an unstable system.
>
>Is there a way to tell the compiler to avoid this behaviour ?

Are you building just from the ports tree or are you using poudriere?

if the former, try unsetting LTO in /etc/make.conf and if you have a 
MAKE_JOBS statement in there, comment it out.

Try installing devel/sccache before your build. Ensure that
ccache is installed too. pay attention to the pkg-message after 
install.

If you're using poudriere, the following settings are relevant:

1. make sure you have ports-mgmt/sccache-overlay installed.

2. in the make.conf for the poudriere jail, have these set:
    SCCACHE_DIR=/var/cache/ccache/sccache
    OVERLAYS+=/usr/local/share/sccache/overlay
    WITH_CCACHE_BUILD=
    CCACHE_DIR=/var/cache/ccache

3. also make sure devel/ccache-static (it *has* to be the -static variant)
    is installed.

To use the sscache overlay, invoke the poudriere build with -O sccache
after installing as per the instructions.

On a rpi4b/8GB (therefore relatively resource constrained) running 14-stable
and poudriere-devel, it has the following settings (relevant to this discussion) 
in poudriere.conf

USE_TMPFS=all
TMPFS_BLACKLIST="rust* llvm* libreo* firef* tex* ungoogled-ch* chromi* gcc* openjdk* electron* iridium"
MAX_FILES=4096
PARALLEL_JOBS=1
PREPARE_PARALLEL_JOBS=2

The following tunables are set in /etc/sysctl.conf 

# filesystem
vm.pageout_oom_seq=120
vm.pfault_oom_attempts=-1
vm.pageout_update_period=0
vfs.zfs.arc.min=536870912
vfs.zfs.arc.max=1073741824

The rpi is clocked to 2.1GHz. It took 9hrs 3 mins to build rust-1.73.0

good luck,
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