linux

docker disk usage

Find large directories

du -ah / | sort -h -r | head -n 20

Find containers using a given volume

docker ps -a --filter volume=<volume>

Remove container and its associated volume

docker rm -v container

See total volume, image, container space

docker system df

See space used per volume

docker system df -v

Remove dangling volumes from disk

docker volume prune

determine which process is listening on a port

sudo netstat -ltnp | grep -w ':80' 

filesystem performance is slow

workaround

Prefer ~/ over /mnt when filesystem performance is needed

sync time

Install ntpdate

sudo apt install ntpdate

Sync

sudo ntpdate time.windows.com

wsl uses all the ram

yolo

Force linux to drop the page cache

echo 1 | sudo tee /proc/sys/vm/drop_caches

limit memory assigned to WSL2 VM

Create a %UserProfile%\.wslconfig file

[wsl2]
memory=6GB
swap=0
localhostForwarding=true

fix clock drift

WSL2 clock drifts if left open when Windows sleeps. Fix with:

sudo hwclock -s

increase number of open files

Running into EMFILE errors because too many files open? (looking at you npm i):

mylimit=8000
sudo prlimit --nofile=$mylimit --pid $$; ulimit -n $mylimit
su $USER

or

sudo prlimit -p "$$" --nofile=10000:10000
exec $SHELL
ulimit -n 10000

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