Extending vmplot

Taking the work already done with vmplot.sh, a useful tool for MySQL performance tuning by Yves and Matt at BigDBAHead, and in true Open Source fashion I’ve enhanced and modified for my own purposes.

These changes include:

  • Error checking for ‘gnuplot’ command on the system
  • Eliminate the first row of sample data, as this is often not a complete sample for the vmstat duration.
  • Created a HTML output file for easy browser viewing
  • Changed Memory scale values from Kilobytes to Megabytes
  • Resizing png’s for optimal 1024×768 display output (2 per row)

Download vmplot

And I get:

So more specifics of what I did.

Install gnuplot.

$ yum install gnuplot

Create vmstat sample file.

vmstat 1 100 > vmstat.out

Generate output graphs (need to work out those warnings)

./vmplot -i vmstat.out -o tmp
Warning: empty y range [0:0], adjusting to [-1:1]
Warning: empty y range [0:0], adjusting to [0:1]

And then I can view via a browser, in this case http://localhost/tmp/vmplot.htm

Some worthwhile references include Gnuplot Reference Manual , Gnuplot Examples and Gnuplot in Action

Tagged with: Databases Linux MySQL Open Source

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