"""
Sets up a subprocess to run sar from the sysstat suite
Default options:
sar -A -f
"""
import os, shutil, subprocess, time
from autotest_lib.client.bin import utils, profiler, os_dep
class sar(profiler.profiler):
"""
The sar command writes to standard output the contents of selected
cumulative activity counters in the operating system. This profiler
executes sar and redirects its output in a file located in the profiler
results dir.
"""
version = 1
def initialize(self, interval=1):
"""
Set sar interval and verify what flags the installed sar supports.
@param interval: Interval used by sar to produce system data.
"""
self.interval = interval
self.sar_path = os_dep.command('sar')
# If using older versions of sar, command below means: Measure default
# params using interval of 1 second continuously. For newer versions,
# behavior has changed - to generate reports continuously just omit the
# count parameter.
t_cmd = self.sar_path + " 1 0"
t_process = subprocess.Popen(t_cmd, shell=True,
stdout=subprocess.PIPE,
stderr=subprocess.PIPE)
# Wait a little to see if process is going to fail or work
time.sleep(3)
if t_process.poll():
# Sar process returned, so 0 doesn't mean generate continuously
self.cmd = self.sar_path + " -o %s %d"
else:
# Sar process didn't return, so 0 means generate continuously
# Just terminate the process
self.cmd = self.sar_path + " -o %s %d 0"
os.kill(t_process.pid, 15)
def start(self, test):
"""
Starts sar subprocess.
@param test: Autotest test on which this profiler will operate on.
"""
logfile = open(os.path.join(test.profdir, "sar"), 'w')
# Save the sar data as binary, convert to text after the test.
raw = os.path.join(test.profdir, "sar.raw")
cmd = self.cmd % (raw, self.interval)
self.sar_process = subprocess.Popen(cmd, shell=True, stdout=logfile,
stderr=subprocess.STDOUT)
def stop(self, test):
"""
Stops profiler execution by sending a SIGTERM to sar process.
@param test: Autotest test on which this profiler will operate on.
"""
try:
os.kill(self.sar_process.pid, 15)
except OSError:
pass
def report(self, test):
"""
Report function. Convert the binary sar data to text.
@param test: Autotest test on which this profiler will operate on.
"""
raw = os.path.join(test.profdir, "sar.raw")
output = os.path.join(test.profdir, "sar")
utils.system('/usr/bin/sar -A -f %s > %s' % (raw, output))