Re: interactive task starvation

Ingo Molnar
2006-03-21T14:54:10Z

* Willy Tarreau <willy@w.ods.org> wrote:

> Ah no, I never use those montruous environments ! xterm is already
> heavy. [...]

[ offtopic note: gnome-terminal developers claim some massive speedups
in Gnome 2.14, and my experiments on Fedora rawhide seem to
corraborate that - gnome-term is now faster (for me) than xterm. ]

> [...] don't you remember, we found that doing "ls" in an xterm was
> waking the xterm process for every single line, which in turn woke the
> X server for a one-line scroll, while adding the "|cat" acted like a
> buffer with batched scrolls. Newer xterms have been improved to
> trigger jump scroll earlier and don't exhibit this behaviour even on
> non-patched kernels. However, sshd still shows the same problem IMHO.

yeah. The "|cat" changes the workload, which gets rated by the scheduler
differently. Such artifacts are inevitable once interactivity heuristics
are strong enough to significantly distort the equal sharing of CPU
time.

Ingo