First rush for the issue #1105. Bug with Process IO when Glances starts

NEWS

@@ -17,6 +17,7 @@ Enhancements and new features:
     * Remove graph export from Glances #1206
     * Add a code of conduct for Glances project's participants #1211
     * Context switches bottleneck identification #1212
+    * Take advantage of the PSUtil issue #1025 (Add process_iter(attrs, ad_value)) #1105
 
 Bugs corrected:
 

glances/processes.py

@@ -149,6 +149,8 @@ def pid_max(self):
                     return int(f.read())
             except (OSError, IOError):
                 return None
+        else:
+            return None
 
     @property
     def max_processes(self):
@@ -414,6 +416,64 @@ def update(self):
         # Update the maximum process ID (pid) number
         self.processcount['pid_max'] = self.pid_max
 
+        # Only work whith PsUtil
+        mandatories_attr = ['cmdline', 'cpu_percent', 'cpu_times',
+                            'io_counters', 'memory_info', 'memory_percent',
+                            'name', 'nice', 'pid',
+                            'ppid', 'status', 'username']
+        self.processlist = [p.info for p in sorted(psutil.process_iter(attrs=mandatories_attr,
+                                                                       ad_value=None),
+                                                   key=lambda p: p.info['cpu_percent'])]
+
+        # Add metadata
+        for proc in self.processlist:
+            proc['time_since_update'] = time_since_update
+            # Status
+            proc['status'] = str(proc['status'])[:1].upper()
+            # Process IO
+            # procstat['io_counters'] is a list:
+            # [read_bytes, write_bytes, read_bytes_old, write_bytes_old, io_tag]
+            # If io_tag = 0 > Access denied (display "?")
+            # If io_tag = 1 > No access denied (display the IO rate)
+            # Availability: all platforms except macOS and Illumos/Solaris
+            if proc['io_counters'] is not None:
+                proc_io = proc['io_counters']
+                io_new = [proc_io.read_bytes, proc_io.write_bytes]
+                # For IO rate computation
+                # Append saved IO r/w bytes
+                try:
+                    proc['io_counters'] = io_new + self.io_old[proc['pid']]
+                except KeyError:
+                    proc['io_counters'] = io_new + [0, 0]
+                # then save the IO r/w bytes
+                self.io_old[proc['pid']] = io_new
+                io_tag = 1
+            else:
+                proc['io_counters'] = [0, 0] + [0, 0]
+                io_tag = 0
+
+            # Append the IO tag (for display)
+            proc['io_counters'] += [io_tag]
+
+    def update_OLD(self):
+        """Update the processes stats."""
+        # Reset the stats
+        self.processlist = []
+        self.reset_processcount()
+
+        # Do not process if disable tag is set
+        if self.disable_tag:
+            return
+
+        # Get the time since last update
+        time_since_update = getTimeSinceLastUpdate('process_disk')
+
+        # Reset the max dict
+        self.reset_max_values()
+
+        # Update the maximum process ID (pid) number
+        self.processcount['pid_max'] = self.pid_max
+
         # Build an internal dict with only mandatories stats (sort keys)
         processdict = {}
         excluded_processes = set()

requirements.txt

@@ -1 +1 @@
-psutil==5.2.2
+psutil==5.4.2