If we have more rows than the max_count in any column, we end up
stretching the histogram vertically, which makes it harder to read.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
If you call ./cairo-perf-print --histogram results.txt, it will then
print a histogram of the results, one per test. Ideally, you should see
a skewed distribution (with a negative skew representing that most results
run in optimal time), but random sampling errors (scheduling,
throttling, general inefficiency etc) will push it more towards a normal
distribution.
For example,
| x |
| x xx |
| x xx |
| x xx |
| xxxx |
| xxxx x |
| x xxxxxx |
| x xxxxxx |
| xxxxxxxxx |
| xxxxxxxxx |
| xxxxxxxxx |
| xxxxxxxxxxxx |
| xxxxxxxxxxxx |
| xxxxxxxxxxxx |
| xxxxxxxxxxxxxx |
|x xxxxxxxxxxxxxx |
|x x xxxxxxxxxxxxxxx |
|x x xxxxxxxxxxxxxxx |
|x x xxxxxxxxxxxxxxxxx |
|xxx x xxxxxxxxxxxxxxxxxxx |
|xxx xxxxxxxxxxxxxxxxxxxxxxxxx |
|xxxxxx xxxx x x x x xxx xx xxxxx xxx x xxx x xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx|
.------------------------------------------------------------------------------.
xlib firefox-fishtank 8298.44 1.53% (829/946)
Starts off reasonably, but quickly deteriorates as the integrated CPU/GPU
overheats and is forced to throttle.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Having spent the last dev cycle looking at how we could specialize the
compositors for various backends, we once again look for the
commonalities in order to reduce the duplication. In part this is
motivated by the idea that spans is a good interface for both the
existent GL backend and pixman, and so they deserve a dedicated
compositor. xcb/xlib target an identical rendering system and so they
should be using the same compositor, and it should be possible to run
that same compositor locally against pixman to generate reference tests.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
P.S. This brings massive upheaval (read breakage) I've tried delaying in
order to fix as many things as possible but now this one patch does far,
far, far too much. Apologies in advance for breaking your favourite
backend, but trust me in that the end result will be much better. :)
When choosing the samples that are not outliers we use a half-open interval
(outlier_min <= x < outlier_max). This causes all of the samples to be
discarded when the interquartile range is 0 because none of them are less
than outlier_max. Fix the problem and make the test more consistent by
using a closed interval (outliner_min <= x <= outlier_max).
We don't need this at this deep level since callers can now
implement this limiting manually since stats.iterations is
now returned. Also, this was interfering with the -i option
to cairo-perf anyway.
