Johannes Müller

Dstat-Plot! (Jan 13, 2016)

tech

dstat monitor plotting script

This ruby script uses GNUPlot through a ruby wrapper (ruby_gnuplot) to plot csv data generated by mvneves’ dstat-monitor.

Pre-requisites and Installation

You need an installation of the ruby programming language, X11, GNUPlot and the ruby_gnuplot gem. The gems csv and optparse are part of the ruby standard library.

To install on a Mac do the following steps:

    1. Install XQuartz from here:
        http://xquartz.macosforge.org/landing/
    2. Install gnuplot with homebrew:
        brew install gnuplot --with-x11
    3. Install gnuplot gem:
        gem install gnuplot

For linux the procedure is

1. Install gnuplot (your distribution might come with it though)
    sudo apt-get install gnuplot
2. Install gnuplot gem:
    gem install gnuplot
3. Install csv gem
    gem install fastercsv

Usage

Usage: dstat_plot.rb [options] -c CATEGORY -f FIELD [directory | file1 file2 ...]
    -v, --verbose                    Output more information
    -i, --invert [VALUE]             Invert the graph such that inverted(x) = VALUE - f(x),
                                     default is 100.
    -n, --no-key                     No plot key is printed.
    -d, --dry                        Dry run. Plot is not saved to file but instead displayed with gnuplot.
    -o, --output FILE|DIR            File or Directory that plot should be saved to.
                                     If a directory is given the filename will be generated.
                                     Default is csv file directory.
    -y, --y-range RANGE              Sets the y-axis range. Default is 105. If a value exceeds
                                     this range, "autoscale" is enabled.
    -c, --category CATEGORY          Select the category.
    -f, --field FIELD                Select the field.
    -h, --help                       Display this screen.

(-c CATEGORY and -f FIELD are mandatory parameters)

The plot is saved as category-field.png in the folder where the csv files are located unless -o PATH explicitly specifies a different destination.

Example

ruby dstat_plot.rb -c "total cpu usage" -f "usr" example.csv

example plot

Possible category - field combinations

(N is the cpu core index for 0..n cores)

Categoriy Field     Categoriy Field  
epoch epoch 0   net/total recv 23
memory usage used 1     send 24
  buff 2   net/eth0 recv 25
  cach 3     send 26
  free 4   dsk/total read 27
swap used 5     writ 28
  free 6   dsk/sda read 29
system int 7     writ 30
  csv 8   io/total read 31
paging in 9     writ 32
  out 10   io/sda read 33
total cpu usage usr 11     writ 34
  sys 12        
  idl 13        
  wai 14        
  hiq 15        
  siq 16        
cpuN usage usr 17        
  sys 18        
  idl 19        
  wai 20        
  hiq 21        
  siq 22