Re: Painfully slow terminal refresh [ Was: Has mutt2 slowed down considerably? ]

[Mayuresh <mayuresh%acm.org@localhost>]

On Sat, Jun 12, 2021 at 04:56:20PM +0700, Gua Chung Lim wrote:
> > On Wed, Apr 21, 2021 at 11:22:31PM +0530, Mayuresh wrote:
> > The issue is not specific to mutt. Even vim, with syntax highlighting
> > shows a painfully slow refresh rate.
> I do not encounter the problems you said.
> % mutt -v | head -n 1
> Mutt 2.0.6 (2021-03-06)
> % vim --version | head -n 1
> VIM - Vi IMproved 8.2 (2019 Dec 12, compiled Mar 31 2021 00:16:48)
> % cat /usr/pkgsrc/CVS/Tag
> Tpkgsrc-2021Q1
> 
> Do you use the same pkgsrc version for both apps and their dependencies?

$ mutt -v | head -n 1
Mutt 2.0.6 (2021-03-06)

$ vim --version | head -n 1
VIM - Vi IMproved 8.1 (2018 May 18, compiled Apr 10 2019 23:29:57)

While mutt problem is (was, see other mails) more consistent, triggering
it in vim depends on amount of syntax highlighting in your file, or may be
on complexity of regexes the highlighter uses or both.

> > I tried experimenting with TERM variable with no luck.
> Is it wsvt25?

It is xterm-256color now, but tried various values. It didn't have any
impact on the problem.

> > The terminal (xterm/uxterm) is launched from Linux and nothing has changed
> > on the Linux device.
> Alright, it is xterm.
> That means you did ssh to NetBSD server. I would suspect your network.
> Do you ssh over WiFi or hard wired cat5e? Is NetBSD server on VM?
> Have you tried logging in directly on NetBSD host and had the test there?

It is wifi and it is VM. But those are not the factors. I can in fact do
vpn and launch a local xterm on the NetBSD VM and the problem persists.

Also as I mentioned, if I cat the output file generated by redirecting
mutt's output it renders instantly.

If I use tty console of the cloud based VM (using a web browser) then
there is no issue. It is super fast.

> > As an experiment, I just redirected mutt output to a file and catted that
> > file. It is rendered instantly with the font colors.
> Well, rendering is fast. Is redirection slow?

Encoding I guess.

> > On Fri, Jun 11, 2021 at 04:30:57PM +0530, Mayuresh wrote:
> > > Update: neomutt works slightly better - perhaps something to do with
> > > ncurses vs curses.
> AFAIK, NetBSD only supports libcurses, there is no ncurses in NetBSD.

Right. But neomutt uses pkg ncurses.

> > On the flip side only one annoying thing I noticed is, if you hit
> > backspace when editing a mail header field, you tend to hold the backspace
> > key to clear the whole line. In that case the back space wraps back to
> > another field and starts working on it instead of stopping after clearing
> > current field. Seems a logged issue on github. I'd try and get used to
> > this behavior as the overall benefits far outweigh this small trouble.
> Does your terminal have some settings like "Delete sends Ctrl-H"?

Backspace and Ctrl-H behave the same.

> Does Ctrl-U delete the entire line?

Oh yes. That works well. Thanks.

-- 
Mayuresh