Create a RamDisk backup DMG image on macOS, detail in Chinese 中文: https://enihsyou.com/2019/02/04/48

backupRamDisk.sh

#!/usr/bin/env bash
DISKNAME=${1-RAM}
IMAGE_LOCATION=${2-"/Users/enihsyou/Library/RAM.dmg"}
DISK_LOCATION=/Volumes/${DISKNAME}

sudo hdiutil create -srcfolder $DISK_LOCATION $IMAGE_LOCATION -ov
sudo chown enihsyou $IMAGE_LOCATION

createRamDisk.sh

#!/usr/bin/env bash
SIZE=${1-2048}
DISKNAME=${2-RAM}

BASE=/Volumes/$DISKNAME
[[ -e $BASE ]] && exit 0

DEVICE_IDENTIFIER=`diskutil info $DISKNAME | sed -n -E 's/^.*Device Identifier:.*(disk.*[0-9]).*/\1/p'`
if [[ -n $DEVICE_IDENTIFIER ]]; then
    hdiutil mountvol $DEVICE_IDENTIFIER
    exit 0
fi

DISK_ID=`hdiutil attach -nomount ram://$(( ${SIZE} * 1024 * 1024 / 512 ))` # a sector is 512 bytes
diskutil partitionDisk $DISK_ID GPT APFS "$DISKNAME" 0

# Backup location
IMAGE_LOCATION=${3-"/Users/enihsyou/Library/RAM.dmg"}
if [ -e $IMAGE_LOCATION ]; then
    asr restore --source $IMAGE_LOCATION --target $BASE --erase --noverify --noprompt
else
    cd $BASE
    mkdir -p Cache/{Chrome,Firefox}
    mkdir -p Compile/Hypers
    mkdir -p Temp/{logs,HDFS/{namenode,datanode}}
fi