Redesign pt-summary

1. Use mktemp, and separate the collection and reporting

Use mktemp to create a temporary directory. Write all samples of output into this directory, and separate the collect and report steps of the tool. The collect stage should simply fill the directory with files, and the report stage should just look at the directory and format a report from it. Make these into separate functions so they can be executed separately. Write tests for the report portion of it. Remove the temporary directory at the end of execution, unless the --tempdir option is given, in which case, the tool should fill the directory with collected data, report, and then save the temporary directory.

2. Report OS-level tuning parameters on important processes

Find the oom_adj value of sshd, and report it. Report if any process is oom_adj'd to -17.

3. Make the tool use long-form command-line options

The tool should accept the standard options:

   --config
   --help
   --sleep how long to sleep for generating "vmstat" output (default 5s)
   --tempdir (no default)
   --version

4. Determine whether anything from Google Code needs attention

The Google Code project for Aspersa has a lot of requests for the "summary" tool, which is this tool's ancestor. Determine whether any bugs or feature requests are worth addressing, and update this spec. See http://code.google.com/p/aspersa/issues/list?can=2&q=summary

5. Improve support for network devices

Use ethtool when available to report on the speed and duplex status (half/full) of each network device (note that device != interface; here we want to report on physical devices)

6. Show amount of configured swap space

Requested by Peter:

# Memory #####################################################
       Total | 11.72G
        Free | 2.26G
        Used | physical = 9.47G, swap = 0.00k, virtual = 9.47G
     Buffers | 131.29M
      Caches | 7.36G
       Dirty | 6356 kB
     UsedRSS | 2.5G

Currently it just shows how much swap is used but not configured.

7. Logical volume group free space

Requested by Peter:

I noticed it does NOT show whenever there is any free space is available at volume group:

# LVM Volumes ################################################
  LV VG Attr LSize Origin Snap% Move Log Copy% Convert
  backup data -wi-ao 320.00G
  mysql data -wi-ao 140.00G
  www data -wi-ao 50.00G

It would be good to get it from vgdisplay:

$ vgdisplay
  --- Volume group ---
  VG Name data
  System ID
  Format lvm2
  Metadata Areas 1
  Metadata Sequence No 481
  VG Access read/write
  VG Status resizable
  MAX LV 0
  Cur LV 3
  Open LV 3
  Max PV 0
  Cur PV 1
  Act PV 1
  VG Size 533.89 GB
  PE Size 4.00 MB
  Total PE 136677
  Alloc PE / Size 130560 / 510.00 GB
  Free PE / Size 6117 / 23.89 GB