WSL2 Cache Memory Auto Release

cache_mon.sh

#!/bin/bash

# Memory threshold
THRESHOLD_AVAIL=10  # MemAvailable
THRESHOLD_FREE=10    # Free

# Loop to test memory
while true; do
    # fetech memory status
    TOTAL_MEM=$(grep MemTotal /proc/meminfo | awk '{print $2 / 1024}')
    AVAIL_MEM=$(grep MemAvailable /proc/meminfo | awk '{print $2 / 1024}')
    FREE_MEM=$(grep MemFree /proc/meminfo | awk '{print $2 / 1024}')

    # comput the usage of memory
    AVAIL_MEM_PCT=$(echo "scale=2; $AVAIL_MEM / $TOTAL_MEM * 100" | bc)
    FREE_MEM_PCT=$(echo "scale=2; $FREE_MEM / $TOTAL_MEM * 100" | bc)

    # check memory
    if (( $(echo "$AVAIL_MEM_PCT < $THRESHOLD_AVAIL" | bc -l) )) || (( $(echo "$FREE_MEM_PCT < $THRESHOLD_FREE" | bc -l) )); then
        echo "Memory cleanup trigger: MemAvailable: $AVAIL_MEM_PCT%, Free: $FREE_MEM_PCT%"
        # clean memory
        echo 3 > /proc/sys/vm/drop_caches
        swapoff -a
        swapon -a
        echo "The cache has been cleared!"
    else
        echo "Memory StatusMemAvailable: $AVAIL_MEM_PCT%, Free: $FREE_MEM_PCT%"
    fi

    # Wait a while for next check
    sleep 60
done