Dstat-Tools

A dstat monitor plotting script for data from multiple nodes of a cluster.

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 ...] or
dstat_plot.rb [options] -l COLUMN [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.
    -t, --title TITLE                Override the default title of the plot.
    -s, --smoothing ALGORITHM        Smooths the graph using the given algorithm.
    -a, --average-over SLICE_SIZE    Calculates the average for slice_size large groups of values.

    -c, --category CATEGORY          Select the category.
    -f, --field FIELD                Select the field.
    -l, --column COLUMN              Select the desired column directly.
    
    -h, --help                       Display this screen.

(-c CATEGORY -f FIELD or -l COLUMN 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

The equivalent with the -l option would be

ruby dstat_plot.rb -l 11 example.csv

Possible category - field combinations

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

Categoriy	Field	Column	Categoriy	Field	Column
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

Smoothing

You can take advantage of a variety of different smoothing algorithms to make your plots more easy on the eye, especially if you’re plotting data from a large number of nodes all in one plot.

To do so use the options –smoothing ALGORITHM when running dstat-plot

Available smoothing algorithms are

unique, frequency, cumulative, cnormal, kdensity, unwrap, csplines, acsplines, mcsplines, bezier, sbezier

As an example

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

will give you the following result smoothing example

Dstat-Tools ()

Pre-requisites and Installation

Usage

Example

Possible category - field combinations

Smoothing