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      1 """
      2 Sets up a subprocess to run sar from the sysstat suite
      3 
      4 Default options:
      5 sar -A -f
      6 """
      7 import os, shutil, subprocess, time
      8 from autotest_lib.client.bin import utils, profiler, os_dep
      9 
     10 
     11 class sar(profiler.profiler):
     12     """
     13     The sar command writes to standard output the contents of selected
     14     cumulative activity counters in the operating system. This profiler
     15     executes sar and redirects its output in a file located in the profiler
     16     results dir.
     17     """
     18     version = 1
     19 
     20     def initialize(self, interval=1):
     21         """
     22         Set sar interval and verify what flags the installed sar supports.
     23 
     24         @param interval: Interval used by sar to produce system data.
     25         """
     26         self.interval = interval
     27         self.sar_path = os_dep.command('sar')
     28         # If using older versions of sar, command below means: Measure default
     29         # params using interval of 1 second continuously. For newer versions,
     30         # behavior has changed - to generate reports continuously just omit the
     31         # count parameter.
     32         t_cmd = self.sar_path + " 1 0"
     33         t_process = subprocess.Popen(t_cmd, shell=True,
     34                                      stdout=subprocess.PIPE,
     35                                      stderr=subprocess.PIPE)
     36         # Wait a little to see if process is going to fail or work
     37         time.sleep(3)
     38         if t_process.poll():
     39             # Sar process returned, so 0 doesn't mean generate continuously
     40             self.cmd = self.sar_path + " -o %s %d"
     41         else:
     42             # Sar process didn't return, so 0 means generate continuously
     43             # Just terminate the process
     44             self.cmd = self.sar_path + " -o %s %d 0"
     45             os.kill(t_process.pid, 15)
     46 
     47 
     48     def start(self, test):
     49         """
     50         Starts sar subprocess.
     51 
     52         @param test: Autotest test on which this profiler will operate on.
     53         """
     54         logfile = open(os.path.join(test.profdir, "sar"), 'w')
     55         # Save the sar data as binary, convert to text after the test.
     56         raw = os.path.join(test.profdir, "sar.raw")
     57         cmd = self.cmd % (raw, self.interval)
     58         self.sar_process = subprocess.Popen(cmd, shell=True, stdout=logfile,
     59                                             stderr=subprocess.STDOUT)
     60 
     61 
     62     def stop(self, test):
     63         """
     64         Stops profiler execution by sending a SIGTERM to sar process.
     65 
     66         @param test: Autotest test on which this profiler will operate on.
     67         """
     68         try:
     69             os.kill(self.sar_process.pid, 15)
     70         except OSError:
     71             pass
     72 
     73     def report(self, test):
     74         """
     75         Report function. Convert the binary sar data to text.
     76 
     77         @param test: Autotest test on which this profiler will operate on.
     78         """
     79         raw = os.path.join(test.profdir, "sar.raw")
     80         output = os.path.join(test.profdir, "sar")
     81         utils.system('/usr/bin/sar -A -f %s > %s' % (raw, output))
     82