pid_fan_control.py

gistfile1.txt

import json
import subprocess
import datetime
import time 

MAX_SPD=80
MIN_SPD=22
ipmi_host="192.168.2.145"
ipmi_pass="xxxxxx"

target_temp=43


def get_temp():
    cmd = "sensors -j"
    x=subprocess.check_output(cmd, shell=True, stderr=subprocess.STDOUT)     
    temps=json.loads(x)
    temp0=(temps['coretemp-isa-0000']['Package id 0']['temp1_input'])
    temp1=(temps['coretemp-isa-0000']['Package id 0']['temp1_input']) #only 1 cpu
    #temp1=(temps['coretemp-isa-0001']['Package id 1']['temp1_input'])
    cpu_temp=(temp0+ temp1)/2
    print("AVG CPU temp:" + str(cpu_temp))
    return cpu_temp

def set_fan(pct_spd):
    cmd_fan="ipmitool -H " + ipmi_host + " -U root -P "+ ipmi_pass + " -I lanplus raw 0x30 0x30 0x01 0x00; sleep 1; ipmitool -H "+ ipmi_host +" -U root -P "+ ipmi_pass +" -I lanplus raw 0x30 0x30 0x02 0xff "

    if pct_spd < MIN_SPD:
        pct_spd = MIN_SPD
    if pct_spd > MAX_SPD:
        pct_spd = MAX_SPD

    x=subprocess.check_output(cmd_fan + hex(pct_spd), shell=True, stderr=subprocess.STDOUT)     


def calculate():
    global target_temp
    last_time = datetime.datetime.now()
    err_sum = 0
    last_err_temp = -1 
    last_spd = 0
    kp = 2
    ki = 3
    kd = 0.1
    while True:
        ts = str(datetime.datetime.now().strftime("%Y-%m-%d_%H:%M:%S"))
        cpu_temp = get_temp()
        now_time = datetime.datetime.now()
        time_diff = (now_time - last_time ).microseconds / 1000000
        
        err_temp = cpu_temp - target_temp
        err_sum  = err_sum+err_temp * time_diff
        if last_err_temp == -1:
            d_err = 0
        else:
            d_err = (err_temp - last_err_temp) / time_diff

        set_spd = round(kp * err_temp + ki * err_sum + kd * d_err)
        if set_spd<MIN_SPD:
            set_spd=MIN_SPD
        if set_spd>MAX_SPD:
            set_spd=MAX_SPD

        print(str(set_spd) + "% PID: ", err_temp, err_sum, d_err, " | ", kp *err_temp, ki * err_temp, kd * d_err)   
        last_err_temp = err_temp
        last_time = now_time
        if abs(set_spd - last_spd)<=1:
            _print=(str(cpu_temp)+" keep   "+ str(last_spd)+"%")
        else:
            set_fan(int(set_spd))
            last_spd = set_spd
            _print=(str(cpu_temp)+" set to "+ str(set_spd)+"%")
        
        _print= ts + " " +_print

        print(_print)
        f=open("/root/last_fanspd.txt", "a")
        f.write(_print + "\n")
        f.close()


        time.sleep(30)


calculate()