5 ms·

I love it, but it's REALLY slow in Windows on the new MS Terminal, which is typically actually quite fast. Noticeably laggy and I can see the screen redraws. An

by nizmow 7y ago

I love it, but it's REALLY slow in Windows on the new MS Terminal, which is typically actually quite fast. Noticeably laggy and I can see the screen redraws. Anyone have any idea why, or how to speed it up?

galacticdessert 7y ago
I also noticed some slowness on Windows, especially in the fuzzy search. Will test later on my private Linux machine for comparison. Overall though, great tool!
JdeBP 7y ago
In the 1980s, full-screen TUI programs did significant work to optimize terminal output. A complete redraw of an 80 by 24 screen at 300 BPS was not quick. So applications normally only wrote changes to the screen, only performing a full redraw when requested by a Control-L input (or some such). Terminals have sped up, but the amount of terminal I/O to draw a screen has increased, too. Nowadays there are lengthy SGR 38/48 sequences for 24-bit RGB, plus the other SGR sequences for attributes, plus of course characters that are now commonly multi-byte UTF-8 encodings, including box drawing characters. So the old considerations of optimizing terminal output still apply nowadays to full-screen TUI applications. Optimize out cursor motions that move to where the cursor currently is; replace absolute motions to nearby positions by shorter relative motion control sequences; optimize out superfluous attribute and colour changes; replace onwards horizontal cursor motions by just rewriting the relevant characters; skip unchanged cells; and so forth. * https://github.com/jdebp/nosh/blob/79b1c0aab9834a09a59e15d47710f355c5c0417a/source/TUIOutputBase.cpp#L143 https://github.com/jdebp/nosh/blob/79b1c0aab9834a09a59e15d47... The Rust full-screen TUI code in Broot (and common Rust libraries) does not do any of this. * https://github.com/Canop/broot/blob/d8ba179946ad10d777f93b4a280f00462a27d393/src/displayable_tree.rs#L181 https://github.com/Canop/broot/blob/d8ba179946ad10d777f93b4a... * https://github.com/crossterm-rs/crossterm/blob/41ff73e3d376382dd102ddea42d9dabb20910a27/src/cursor.rs#L62 https://github.com/crossterm-rs/crossterm/blob/41ff73e3d3763... When it is a Win32 application, it uses console I/O and this does not matter quite as much, although it's still a waste of system call context switches to overwrite a console screen buffer with what is already there. But when it is using terminal I/O this matters significantly. The Rust terminal handling is actually fairly poor overall. This list, for example, is in reality a lot longer. The terminfo database records a lot more terminal types that understand these escape sequences. "putty" for one egregiously missing example. * https://github.com/crossterm-rs/crossterm/blob/41ff73e3d376382dd102ddea42d9dabb20910a27/src/ansi_support.rs#L60 https://github.com/crossterm-rs/crossterm/blob/41ff73e3d3763... * https://invisible-island.net/ncurses/terminfo.ti.html#tic-putty https://invisible-island.net/ncurses/terminfo.ti.html#tic-pu... Personally, rather than treat lack of capability as the norm with a paltry list of exceptions, I prefer the opposite assumption that (except for "dumb") the world has nowadays reached 1976 capability levels. (-: * https://github.com/jdebp/nosh/blob/79b1c0aab9834a09a59e15d47710f355c5c0417a/source/TerminalCapabilities.cpp#L54 https://github.com/jdebp/nosh/blob/79b1c0aab9834a09a59e15d47...
OvermindDL1 7y ago
Loving it, but it's very slow on refresh on Linux over ssh as well. Looks like it's doing full screen refreshes on every change instead of just using delta's that tui apps should be doing.

by nizmow 7y ago

galacticdessert 7y ago

I also noticed some slowness on Windows, especially in the fuzzy search. Will test later on my private Linux machine for comparison. Overall though, great tool!

JdeBP 7y ago

In the 1980s, full-screen TUI programs did significant work to optimize terminal output. A complete redraw of an 80 by 24 screen at 300 BPS was not quick. So applications normally only wrote changes to the screen, only performing a full redraw when requested by a Control-L input (or some such). Terminals have sped up, but the amount of terminal I/O to draw a screen has increased, too. Nowadays there are lengthy SGR 38/48 sequences for 24-bit RGB, plus the other SGR sequences for attributes, plus of course characters that are now commonly multi-byte UTF-8 encodings, including box drawing characters. So the old considerations of optimizing terminal output still apply nowadays to full-screen TUI applications. Optimize out cursor motions that move to where the cursor currently is; replace absolute motions to nearby positions by shorter relative motion control sequences; optimize out superfluous attribute and colour changes; replace onwards horizontal cursor motions by just rewriting the relevant characters; skip unchanged cells; and so forth. * https://github.com/jdebp/nosh/blob/79b1c0aab9834a09a59e15d47710f355c5c0417a/source/TUIOutputBase.cpp#L143 https://github.com/jdebp/nosh/blob/79b1c0aab9834a09a59e15d47... The Rust full-screen TUI code in Broot (and common Rust libraries) does not do any of this. * https://github.com/Canop/broot/blob/d8ba179946ad10d777f93b4a280f00462a27d393/src/displayable_tree.rs#L181 https://github.com/Canop/broot/blob/d8ba179946ad10d777f93b4a... * https://github.com/crossterm-rs/crossterm/blob/41ff73e3d376382dd102ddea42d9dabb20910a27/src/cursor.rs#L62 https://github.com/crossterm-rs/crossterm/blob/41ff73e3d3763... When it is a Win32 application, it uses console I/O and this does not matter quite as much, although it's still a waste of system call context switches to overwrite a console screen buffer with what is already there. But when it is using terminal I/O this matters significantly. The Rust terminal handling is actually fairly poor overall. This list, for example, is in reality a lot longer. The terminfo database records a lot more terminal types that understand these escape sequences. "putty" for one egregiously missing example. * https://github.com/crossterm-rs/crossterm/blob/41ff73e3d376382dd102ddea42d9dabb20910a27/src/ansi_support.rs#L60 https://github.com/crossterm-rs/crossterm/blob/41ff73e3d3763... * https://invisible-island.net/ncurses/terminfo.ti.html#tic-putty https://invisible-island.net/ncurses/terminfo.ti.html#tic-pu... Personally, rather than treat lack of capability as the norm with a paltry list of exceptions, I prefer the opposite assumption that (except for "dumb") the world has nowadays reached 1976 capability levels. (-: * https://github.com/jdebp/nosh/blob/79b1c0aab9834a09a59e15d47710f355c5c0417a/source/TerminalCapabilities.cpp#L54 https://github.com/jdebp/nosh/blob/79b1c0aab9834a09a59e15d47...

OvermindDL1 7y ago

Loving it, but it's very slow on refresh on Linux over ssh as well. Looks like it's doing full screen refreshes on every change instead of just using delta's that tui apps should be doing.