在守护进程中使用pigpio库时，"initMboxBlock: initMboxBlock失败“和”无法锁定/var/run/Pipio.id“

Question

我正在使用node.js编写一个守护进程，运行在systemd下，它将使用监测树莓皮2B上电源电压的状态。

我正在使用node.js包装器到猪皮库

我开始使用的代码如下：

var Gpio = require('pigpio').Gpio,
gpio;

gpio = new Gpio(35);

const checkIntervalDuringBrownout   = 5000;
const checkIntervalDuringGoodSupply = 100;
var timer = 100;

function startTimer() {
  setTimeout(function() {
    var brownoutState = isUnderVoltage();

    if(brownoutState) {
      console.log("Brownout - telling the syslog ...");
      console.log("Brownout ... Power Supply Voltage went below 4.63 V");
      timer = checkIntervalDuringBrownout;
    }
    else {
      timer = checkIntervalDuringGoodSupply;
   }
    startTimer();
  }, timer);
}

function isUnderVoltage() {
  var ledStatus = gpio.digitalRead(); 
  if(ledStatus === 1) {
    return 0;
  }
  else if (ledStatus === 0) {
    //console.log("brownout");
    return 1;
  }
  else {
    console.log("We got neither a 1 or a 0: ", ledStatus);
  }
}

startTimer();

在syslog中得到神秘的错误消息：

    Aug  2 00:22:10 chintu systemd[1]: Started Brownout Monitor and Logger written using node.js.
Aug  2 00:22:11 chintu brownout-monitor[5203]: 2017-08-02 00:22:11 initMboxBlock: init mbox zaps failed
Aug  2 00:22:11 chintu brownout-monitor[5203]: /home/pi/sandbox/raspi2-power-monitor/node_modules/pigpio/pigpio.js:11
Aug  2 00:22:11 chintu brownout-monitor[5203]: pigpio.gpioInitialise();
Aug  2 00:22:11 chintu brownout-monitor[5203]: ^
Aug  2 00:22:11 chintu brownout-monitor[5203]: Error: pigpio error -1 in gpioInitialise
Aug  2 00:22:11 chintu brownout-monitor[5203]: at Error (native)
Aug  2 00:22:11 chintu brownout-monitor[5203]: at initializePigpio (/home/pi/sandbox/raspi2-power-monitor/node_modules/pigpio/pigpio.js:11:12)
Aug  2 00:22:11 chintu brownout-monitor[5203]: at new Gpio (/home/pi/sandbox/raspi2-power-monitor/node_modules/pigpio/pigpio.js:25:3)

和

Aug  2 00:17:11 chintu systemd[1]: Starting Brownout Monitor and Logger written using node.js...
Aug  2 00:17:11 chintu systemd[1]: Started Brownout Monitor and Logger written using node.js.
Aug  2 00:17:12 chintu brownout-monitor[4555]: 2017-08-02 00:17:12 initInitialise: Can't lock /var/run/pigpio.pid
Aug  2 00:17:12 chintu brownout-monitor[4555]: /home/pi/sandbox/raspi2-power-monitor/node_modules/pigpio/pigpio.js:11
Aug  2 00:17:12 chintu brownout-monitor[4555]: pigpio.gpioInitialise();
Aug  2 00:17:12 chintu brownout-monitor[4555]: ^
Aug  2 00:17:12 chintu brownout-monitor[4555]: Error: pigpio error -1 in gpioInitialise
Aug  2 00:17:12 chintu brownout-monitor[4555]: at Error (native)
Aug  2 00:17:12 chintu brownout-monitor[4555]: at initializePigpio (/home/pi/sandbox/raspi2-power-monitor/node_modules/pigpio/pigpio.js:11:12)
Aug  2 00:17:12 chintu brownout-monitor[4555]: at new Gpio (/home/pi/sandbox/raspi2-power-monitor/node_modules/pigpio/pigpio.js:25:3)
Aug  2 00:17:12 chintu brownout-monitor[4555]: at Object.<anonymous> (/home/pi/sandbox/raspi2-power-monitor/index.js:7:8)
Aug  2 00:17:12 chintu brownout-monitor[4555]: at Module._compile (module.js:570:32)
Aug  2 00:17:12 chintu brownout-monitor[4555]: at Object.Module._extensions..js (module.js:579:10)
Aug  2 00:17:12 chintu brownout-monitor[4555]: at Module.load (module.js:487:32)
Aug  2 00:17:12 chintu brownout-monitor[4555]: at tryModuleLoad (module.js:446:12)
Aug  2 00:17:12 chintu brownout-monitor[4555]: at Function.Module._load (module.js:438:3)
Aug  2 00:17:12 chintu brownout-monitor[4555]: at Module.runMain (module.js:604:10)
Aug  2 00:17:12 chintu systemd[1]: brownout-monitor.service: main process exited, code=exited, status=1/FAILURE
Aug  2 00:17:12 chintu systemd[1]: Unit brownout-monitor.service entered failed state.

查找这些错误，带我看了一页，其中的解决方案说-

我必须检查代码，但最有可能的是GPU (分配mbox内存)没有空闲内存。

怎么解决这个问题呢？

Answer 1

修复错误的解决方案是：

处理systemd发送到节点进程的信号，并确保pigpio库使用处理程序中的pigpio.terminate()调用完成干净的终止。

process.on('SIGHUP', shutdown);
process.on('SIGINT', shutdown);
process.on('SIGCONT', shutdown);
process.on('SIGTERM', shutdown);

function shutdown() {
  pigpio.terminate();
  clearInterval(timerVar);
  console.log('raspi2-brownout-watcher must exit, performed cleanup.');
  process.exit(0);
}