For keybase filesystem (kbfs) mirroring

parasync.bash

#!/usr/bin/env bash
# EX
# bash parasync.bash /run/user/1001/keybase/kbfs/team/team/ ~/mnt/ 10 /run/user/1001/keybase/kbfs/team/team/ -rvWtS --delete --force --progress --partial
Usage() {
#Help
cat <<'EOF'
./parasync.bash [from] [to] [parallels] [source include_dir] [rsync option]

  Number of parallels:
    def | default (10)
    num | set to num
  rsync option:
    '--relative --stats --safe-links --ignore-existing --human-readable'
    are already specfied.
  Requrements:
    - bash
    - rsync
    - parallel
EOF
}
# Env
  export TEMP_DIR="$(mktemp -d)"
	echo "TEMPDIR: $TEMP_DIR"
  if [ "$3" = "def" ];then
		export PARA_NUM=10
  else
		export PARA_NUM=$3
	fi
	for n in $(seq 5 $#)
	do
		export RSYNC_OPT="${RSYNC_OPT} $(eval echo -n '$'$n)"
	done
# Help
  if   [ "$1" = "-h" ];then
    Usage ; exit 0
  elif [ "$1" = "--help" ];then
    Usage ; exit 0
  elif [ -z "$1" ];then
    echo 'Argument needed.' ; exit 1
  fi
Prompt() {
#Run
	if [ "$PARASYNC_SKIP_PROMPT" = "true" ];then
		:
	else
		read -p "Are you sure? | Y/n > " sttprompt
		if [ "$sttprompt" = "n" ];then
			echo 'Aborted' ; exit 0
		fi
	fi
}
# Run
	export FROMDIR="$PWD"
  cd $4
	rsync $(echo -n $RSYNC_OPT|tr ' ' ' ') --stats --safe-links --ignore-existing --dry-run --human-readable \
	$1 $2 | tee $TEMP_DIR/queue.list
	Prompt
  echo $PWD
	cat $TEMP_DIR/queue.list | \
  parallel --will-cite -j 6 rsync $(echo -n $RSYNC_OPT|tr ' ' ' ') --relative --stats --safe-links --ignore-existing --human-readable {} \
	$2 | tee $TEMP_DIR/result.log
	cd $FROMDIR

https://git.io/parasync