can't read x-axis on output graphs for bench_chart.

Bench Chart rely on Chart module.
http://stackoverflow.com/questions/786789/vertical-labels-with-google-ch...
It says that with Google Charts API it's not possible to create vertical x-axis.
Can you check the other Charts available?

Created ticket against Chart module: #1146526: Vertical or more readable x-axis with Google Charts?

Something I don't understand: project page states dependency on http://drupal.org/project/charts, not http://drupal.org/project/chart, so shouldn't the issue mentioned in#1 be moved to charts module also?

The screenshot is from bench_chart sub-module, so I think the problem could within that module, how it implements line2D by using charts_chart() in bench_chart_charts.inc.
However checking it further this seems to be related Charts issues: #2223819: set interval for horizontal axis and #2052723: Limit the labels on the X-Axis which both they're duplicated of #1237096: Graph node input over time (support date formatting on a continuous axis).
So I think it's better to set it as duplicate to that. Once it's fixed, then eventually we can think of back-porting it to 6.x if anybody still using it.

Seems OK for me Rafal. Happy my previous comment somehow helped to get an issue from 4 years ago moving again, and somehow even close it as per your additional comment.