iotop/vmstat.py

   1 # This program is free software; you can redistribute it and/or modify
   2 # it under the terms of the GNU General Public License as published by
   3 # the Free Software Foundation; either version 2 of the License, or
   4 # (at your option) any later version.
   5 #
   6 # This program is distributed in the hope that it will be useful,
   7 # but WITHOUT ANY WARRANTY; without even the implied warranty of
   8 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   9 # GNU Library General Public License for more details.
  10 #
  11 # You should have received a copy of the GNU General Public License
  12 # along with this program; if not, write to the Free Software
  13 # Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  14 #
  15 # See the COPYING file for license information.
  16 #
  17 # Copyright (c) 2007 Guillaume Chazarain <guichaz@gmail.com>
  18
  19 import os
  20
  21 class VmStat(object):
  22     def __init__(self):
  23         self.vmstat_file = open('/proc/vmstat')
  24         self.vmstat = self.read()
  25
  26     def read(self):
  27         def extract(line):
  28             return int(line.split()[1]) * 1024
  29
  30         for line in self.vmstat_file:
  31             if line.startswith('pgpgin '):
  32                 pgpgin = extract(line)
  33                 break
  34
  35         for line in self.vmstat_file:
  36             if line.startswith('pgpgout '):
  37                 pgpgout = extract(line)
  38                 break
  39
  40         self.vmstat_file.seek(0)
  41         return pgpgin, pgpgout
  42
  43     def delta(self):
  44         now = self.read()
  45         delta = now[0] - self.vmstat[0], now[1] - self.vmstat[1]
  46         self.vmstat = now
  47         return delta
  48