What does this log mean?

vutran asked:

While my application is running (with a lot of traffic), I see this in error log but I dont even understand what it is about. I guess it’s optimizing some configuration but I need a more formal explaination.

App 13214 stderr: Trying:
App 13214 stderr:   zc = 9  zm = 9  zs = 0  f = 0
App 13214 stderr:       IDAT size = 5698
App 13214 stderr:   zc = 9  zm = 8  zs = 0  f = 0
App 13214 stderr:       IDAT size = 5698
App 13214 stderr:   zc = 9  zm = 9  zs = 1  f = 0
App 13214 stderr:       IDAT size = 5561
App 13214 stderr:   zc = 9  zm = 8  zs = 1  f = 0
App 13214 stderr:       IDAT size = 5561
App 13214 stderr:   zc = 1  zm = 9  zs = 2  f = 0
  zc = 1  zm = 8  zs = 2  f = 0
  zc = 9  zm = 9  zs = 3  f = 0
  zc = 9  zm = 8  zs = 3  f = 0
  zc = 9  zm = 9  zs = 0  f = 1
  zc = 9  zm = 8  zs = 0  f = 1
  zc = 9  zm = 9  zs = 1  f = 1
  zc = 9  zm = 8  zs = 1  f = 1
  zc = 1  zm = 9  zs = 2  f = 1
  zc = 1  zm = 8  zs = 2  f = 1
  zc = 9  zm = 9  zs = 3  f = 1
  zc = 9  zm = 8  zs = 3  f = 1
  zc = 9  zm = 9  zs = 0  f = 2
  zc = 9  zm = 8  zs = 0  f = 2
  zc = 9  zm = 9  zs = 1  f = 2
  zc = 9  zm = 8  zs = 1  f = 2
  zc = 1  zm = 9  zs = 2  f = 2
  zc = 1  zm = 8  zs = 2  f = 2
  zc = 9  zm = 9  zs = 3  f = 2
  zc = 9  zm = 8  zs = 3  f = 2
  zc = 9  zm = 9  zs = 0  f = 3
  zc = 9  zm = 8  zs = 0  f = 3
  zc = 9  zm = 9  zs = 1  f = 3
  zc = 9  zm = 8  zs = 1  f = 3
  zc = 1  zm = 9  zs = 2  f = 3
  zc = 1  zm = 8  zs = 2  f = 3
  zc = 9  zm = 9  zs = 3  f = 3
  zc = 9  zm = 8  zs = 3  f = 3
  zc = 9  zm = 9  zs = 0  f = 4
  zc = 9  zm = 8  zs = 0  f = 4
  zc = 9  zm = 9  zs = 1  f = 4
  zc = 9  zm = 8  zs = 1  f = 4
  zc = 1  zm = 9  zs = 2  f = 4
  zc = 1  zm = 8  zs = 2  f = 4
  zc = 9  zm = 9  zs = 3  f = 4
  zc = 9  zm = 8  zs = 3  f = 4
  zc = 9  zm = 9  zs = 0  f = 5
  zc = 9  zm = 8  zs = 0  f = 5
  zc = 9  zm = 9  zs = 1  f = 5
  zc = 9  zm = 8  zs = 1  f = 5
  zc = 1  zm = 9  zs = 2  f = 5
  zc = 1  zm = 8  zs = 2  f = 5
  zc = 9  zm = 9  zs = 3  f = 5
  zc = 9  zm = 8  zs = 3  f = 5

My answer:


That is verbose output from the optipng utility for shrinking PNG images. You may suppress this output with the --quiet option. Though probably one of your gems is calling it and you have little control over whether it passes the option.


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