### Dstat most expensive process plugin
### Displays the name of the most expensive process
###
### Authority: dag@wieers.com

global string
import string

class dstat_app(dstat):
	def __init__(self):
		self.name = 'most expensive'
		self.format = ('s', 18, 0)
		self.nick = ('process',)
		self.vars = self.nick
		self.pid = str(os.getpid())
		self.cn1 = {}; self.cn2 = {}; self.val = {}

	def extract(self):
		max = 0.0
		for pid in os.listdir('/proc/'):
			try: int(pid)
			except: continue
			if os.path.exists('/proc/%s/stat' % pid):
				if pid == self.pid: continue
				if not self.cn1.has_key(pid):
					self.cn1[pid] = 0

				### Using dopen() will cause too many open files
#				l = string.split(dopen('/proc/%s/stat' % pid).read())
				l = string.split(open('/proc/%s/stat' % pid).read())
				if len(l) < 15: continue
				self.cn2[pid] = int(l[13]) + int(l[14])
				usage = (self.cn2[pid] - self.cn1[pid]) * 1.0 / tick

				### Get the process that spends the most jiffies
				if usage > max:
					max = usage
					self.val['name'] = l[1][1:-1]
					self.val['pid'] = pid

		if max == 0.0:
			self.val['process'] = ''
		else:
			### If the name is a known interpreter, take the second argument from the cmdline
			if self.val['name'] in ('bash', 'csh', 'ksh', 'perl', 'python', 'sh'):
				### Using dopen() will cause too many open files
#				l = string.split(dopen('/proc/%s/cmdline' % self.val['pid']).read(), '\0')
				l = string.split(open('/proc/%s/cmdline' % self.val['pid']).read(), '\0')
				if len(l) > 2:
					self.val['name'] = os.path.basename(l[1])

#				l = l.reverse()
#				for x in l:
#					print x
#					if x[0] != '-':
#						self.val['name'] = os.path.basename(x)
#						break

			### Show yellow usage
			self.val['process'] = '%-*s%s%3d' % (self.format[1]-3, self.val['name'], ansi['yellow'], round(max))

			### Debug (show PID)
#			self.val['process'] = '%*s %-*s' % (5, self.val['pid'], self.format[1]-6, self.val['name'])

		if step == op.delay:
			self.cn1.update(self.cn2)

# vim:ts=4:sw=4