Fix Fast Ping (#12509)

Recent Laravel version update broke ping.php by now serializing the PingCheck job.
Store process parameters instead of process object.

app/Jobs/PingCheck.php

@@ -43,7 +43,8 @@ class PingCheck implements ShouldQueue
 {
     use Dispatchable, InteractsWithQueue, Queueable, SerializesModels;
 
-    private $process;
+    private $command;
+    private $wait;
     private $rrd_tags;
 
     /** @var \Illuminate\Database\Eloquent\Collection List of devices keyed by hostname */
@@ -80,11 +81,8 @@ class PingCheck implements ShouldQueue
         $timeout = Config::get('fping_options.timeout', 500); // must be smaller than period
         $retries = Config::get('fping_options.retries', 2);  // how many retries on failure
 
-        $cmd = ['fping', '-f', '-', '-e', '-t', $timeout, '-r', $retries];
-
-        $wait = Config::get('rrd.step', 300) * 2;
-
-        $this->process = new Process($cmd, null, null, null, $wait);
+        $this->command = ['fping', '-f', '-', '-e', '-t', $timeout, '-r', $retries];
+        $this->wait = Config::get('rrd.step', 300) * 2;
     }
 
     /**
@@ -98,7 +96,9 @@ class PingCheck implements ShouldQueue
 
         $this->fetchDevices();
 
-        d_echo($this->process->getCommandLine() . PHP_EOL);
+        $process = new Process($this->command, null, null, null, $this->wait);
+
+        d_echo($process->getCommandLine() . PHP_EOL);
 
         // send hostnames to stdin to avoid overflowing cli length limits
         $ordered_device_list = $this->tiered->get(1, collect())->keys()// root nodes before standalone nodes
@@ -106,10 +106,10 @@ class PingCheck implements ShouldQueue
             ->unique()
             ->implode(PHP_EOL);
 
-        $this->process->setInput($ordered_device_list);
-        $this->process->start(); // start as early as possible
+        $process->setInput($ordered_device_list);
+        $process->start(); // start as early as possible
 
-        foreach ($this->process as $type => $line) {
+        foreach ($process as $type => $line) {
             d_echo($line);
 
             if (Process::ERR === $type) {