* Arnaldo Carvalho de Melo <a...@infradead.org> wrote:
> Em Thu, Mar 05, 2015 at 11:32:13AM +0100, Ingo Molnar escreveu:
> > Boris reported that 'perf top' is unusable on his default 'black on
> > white' terminal, which uses (eye friendly) light-grey as a background
> > color.
> >
> > The reason is that the TUI cursor for the current selection line uses
> > HE_COLORSET_SELECTED, and that has a default background color of
> > 'lightgrey' - which is a common terminal background choice and thus
> > the colors conflict.
> >
> > Use yellow as the background color instead: that should be an uncommon
> > terminal background, yet it's still ergonomic on both black and
> > white/grey terminals.
> >
> > [ It would be a better solution to straight out detect color
> > collisions and resolve them reasonably by converting them to RGB and
> > calculating color space distances, but I was unable to find
> > proper documentation for SLtt_get_color_object() to recover the
> > current color scheme so I gave up ... Yellow works well enough. ]
>
> Thanks, applying.
>
> BTW, I started with newt, thinking it would give me good widgets,
> only to, after having reached its limitations write my own, this
> time just on, like newt, top of slang's tui libraries, eventually I
> think I'll move to ncurses or even just use the kernel tty interface
> directly ;-)
LOL! :-)
Btw., a related problem: X terminals are pretty high overhead
unfortunately, I cringe every time I run 'perf top' on a very fast
system:
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
4240 mingo 20 0 1031088 176112 106648 S 5.9 0.3 101:54.30 konsole
1985 root 20 0 649412 194760 157464 S 3.0 0.3 41:49.94 Xorg
2395 mingo 20 0 2283956 526044 127108 S 2.0 0.8 34:40.23 compiz
13258 mingo 20 0 207588 70916 12112 S 1.3 0.1 0:03.01 perf
10%+ of GUI CPU overhead with a refresh every 2 seconds (i.e. only 0.5
fps) - ridiculous!
So to fix this I think we eventually want a raw OpenGL client for
local system 'perf top' use and such: that would be (by far) the
lowest overhead UI interface to run profiling from without disturbing
the system, with UI overhead in the ~1% range at most.
Raw (no toolkits) OpenGL would also allow us to do a lot of other UI
and performance tricks.
Would you have any fundamental objections against OpenGL UI clients?
Thanks,
Ingo
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
