Responses following...

On Mar 13, 2013, at 6:32 AM, John Mazzitelli <mazz@redhat.com> wrote:

I have two comments on the new graphs.

1) The fonts in the X and Y axes are fat and fuzzy. Is there anyway we can use better fonts? Its hard to read some of the labels because the letters are so fat and fuzzy they bleed into one other.

See attached font.png as an example. You have to look really hard to read what that Y-axis label is saying. And even though the X-Axis times are readable, they aren't crisp and easy to read.
Agreed. We had another font originally that was clean. However, in one of the meetings we received feedback that the fonts should match the rest of the page so the font is now 10pt "Arial, Verdana, sans-serif". But I agree is not as clear as the rest of the page; probably due to the fact that it is SVG and not HTML so the rendering process is slightly different. I will play around with cleaner fonts. This should be fixed.

2) I think the lines that connect the bars should definitely not go down to zero for the "grey" bars - that is, for the times when no collection was made. The lines infer the value of the metric is zero when that is not true - we have no idea what the value is for the metric at that time. To show the line connecting at 0 is misleading. When you look at the graph, they all look saw toothed - as if the metric values are some number, then 0, then some number, then 0 which is not necessarily the case (and probably isn't the case). We should only connect the bars where we have actual values.
The issue with the lines connecting the bars not going down to zero also came up in a charting meeting. Originally, we assumed the values for the connecting lines to be whatever the last value was. For instance, in the little graph below, the 2 bars following the first bar had averages of 600 just like the first bar. However, we don't actually know what the value of missing data bars is so making the assuming that is some value seemed dangerous. The least dangerous thing to do was to assume zero for values that we don't actually know. 
I agree that the sawtoothing is not really helping to visualize directionality, so we could try to algorithmically determine this sawtoothing and turn off the average lines when we sense there is no directionality in the chart (too much noise to be trendy)? 


See sawtooth.png for what I'm talking about. <sawtooth.png><font.png>_______________________________________________
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