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import logging
import os
from datetime import timedelta, datetime
from landscape.lib.timestamp import to_timestamp
from landscape.lib.jiffies import detect_jiffies
# FIXME: It'd be nice to avoid having library code which depends on
# landscape-specific modules.
from landscape.monitor.computeruptime import BootTimes, get_uptime
STATES = {"R (running)": "R",
"D (disk sleep)": "D",
"S (sleeping)": "S",
"T (stopped)": "T",
"T (tracing stop)": "I",
"X (dead)": "X",
"Z (zombie)": "Z"}
class ProcessInformation(object):
def __init__(self, proc_dir="/proc", jiffies=None, boot_time=None,
uptime=None):
"""
The uptime parameter here is only used for faking uptime in tests.
"""
if boot_time is None:
boot_time = BootTimes().get_last_boot_time()
if boot_time is not None:
boot_time = datetime.utcfromtimestamp(boot_time)
self._boot_time = boot_time
self._proc_dir = proc_dir
self._jiffies_per_sec = jiffies or detect_jiffies()
self._uptime = uptime
def get_all_process_info(self):
"""Get process information for all processes on the system."""
for filename in os.listdir(self._proc_dir):
try:
process_id = int(filename)
except ValueError:
continue
process_info = self.get_process_info(process_id)
if process_info:
yield process_info
def get_process_info(self, process_id):
"""
Parse the /proc/<pid>/cmdline and /proc/<pid>/status files for
information about the running process with process_id.
The /proc filesystem doesn't behave like ext2, open files can disappear
during the read process.
"""
cmd_line_name = ""
process_dir = os.path.join(self._proc_dir, str(process_id))
process_info = {"pid": process_id}
try:
file = open(os.path.join(process_dir, "cmdline"), "r")
try:
# cmdline is a \0 separated list of strings
# We take the first, and then strip off the path, leaving us with
# the basename.
cmd_line = file.readline()
cmd_line_name = os.path.basename(cmd_line.split("\0")[0])
finally:
file.close()
file = open(os.path.join(process_dir, "status"), "r")
try:
for line in file:
parts = line.split(":", 1)
if parts[0] == "Name":
process_info["name"] = (cmd_line_name.strip() or
parts[1].strip())
elif parts[0] == "State":
state = parts[1].strip()
process_info["state"] = STATES[state]
elif parts[0] == "Uid":
value_parts = parts[1].split()
process_info["uid"] = int(value_parts[0])
elif parts[0] == "Gid":
value_parts = parts[1].split()
process_info["gid"] = int(value_parts[0])
elif parts[0] == "VmSize":
value_parts = parts[1].split()
process_info["vm-size"] = int(value_parts[0])
break
finally:
file.close()
file = open(os.path.join(process_dir, "stat"), "r")
try:
# These variable names are lifted directly from proc(5)
# utime: The number of jiffies that this process has been scheduled in
# user mode.
# stime: The number of jiffies that this process has been scheduled in
# kernel mode.
# cutime: The number of jiffies that this process's waited-for children
# have been scheduled in user mode.
# cstime: The number of jiffies that this process's waited-for children
# have been scheduled in kernel mode.
parts = file.read().split()
start_time = int(parts[21])
utime = int(parts[13])
stime = int(parts[14])
uptime = self._uptime or get_uptime()
pcpu = calculate_pcpu(utime, stime, uptime,
start_time, self._jiffies_per_sec)
process_info["percent-cpu"] = pcpu
delta = timedelta(0, start_time // self._jiffies_per_sec)
if self._boot_time is None:
logging.warning("Skipping process (PID %s) without boot time.")
return None
process_info["start-time"] = to_timestamp(self._boot_time + delta)
finally:
file.close()
except IOError:
# Handle the race that happens when we find a process
# which terminates before we open the stat file.
return None
assert("pid" in process_info and "state" in process_info
and "name" in process_info and "uid" in process_info
and "gid" in process_info and "start-time" in process_info)
return process_info
def calculate_pcpu(utime, stime, uptime, start_time, hertz):
"""
Implement ps' algorithm to calculate the percentage cpu utilisation for a
process.::
unsigned long long total_time; /* jiffies used by this process */
unsigned pcpu = 0; /* scaled %cpu, 99 means 99% */
unsigned long long seconds; /* seconds of process life */
total_time = pp->utime + pp->stime;
if(include_dead_children) total_time += (pp->cutime + pp->cstime);
seconds = seconds_since_boot - pp->start_time / hertz;
if(seconds) pcpu = (total_time * 100ULL / hertz) / seconds;
if (pcpu > 99U) pcpu = 99U;
return snprintf(outbuf, COLWID, "%2u", pcpu);
"""
pcpu = 0
total_time = utime + stime
seconds = uptime - (start_time / hertz)
if seconds:
pcpu = total_time * 100 / hertz / seconds
return round(max(min(pcpu, 99.0), 0), 1)
