Re: About render speed

[Rui Tiago Cação Matos <tiagomatos gmail com>]

On 20 May 2012 15:59, Weng Xuetian <wengxt gmail com> wrote:
> I'm implementing an extension that may need to update a window very
> frequenctly, say maybe 10 times per second. (Please don't ask about reducing
> the frequency, this is based on an very rapid user input and it need to be
> updated in time to give user correct reaction.)
>
> I'm using 10 St.Text and all of them will be updated, but I found it could not
> be updated in time (very obvious delay, say second level).

I don't have a ready answer but I'd like to point that there is a
lower bound on the achievable latency with the current architecture
just due to the various context switches that must occur for you to
see stuff on the screen after the user presses a key:

X server > App > DBus daemon > Input Method daemon > DBus daemon >
gnome-shell > X server

So that's 6 context switches per event. Now, there probably is some
low hanging fruit that could greatly improve things even with the
current architecture but there will be a lower bound which might still
be noticeable.

Rui