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mirror of https://github.com/wez/wezterm.git synced 2024-12-23 13:21:38 +03:00
wezterm/termwiz
Wez Furlong 35ce2fe74d trim heap usage
I spent a few hours in heap profilers.  What I found was:

* Inefficient use of heap when building up runs of
  `Action::Print(char)`.
    -> Solve by adding `Action::PrintString(String)`
  and accumulating utf8 bytes rather than u32 codepoints.
* Inefficient use of heap when building Quad buffers: the default
  exponential growth of `Vec` tended to waste 40%-75% of the allocated
  capacity, and since we could keep ~1024 of these in cache, there's
  a lot of potential for waste.
   -> Solve by bounding the growth to 64 at a time.  This has similar
   characteristics to exponential growth at the default 80x24 terminal
   size.  May need to add a config option for this step size for users
   with very large terminals.
* Lazy eviction from the LFU caches. The underlying cache advisor is
  somewhat probabilistic and has a minimum cache size of 256, making
  it difficult to maintain low heap utilization.
   -> Solve by replacing it with a very simple LFU algorithm. It doesn't
   seem to hurt much at the default terminal size with the default
   cache sizes.  If we make the cache sizes smaller, its overhead is
   reduced.

Some further experimentation is needed to adjust defaults, but this
should help reduce heap usage.

refs: https://github.com/wez/wezterm/issues/2626
2022-10-22 17:10:36 -07:00
..
benches termwiz: add bench for Cell creation/drop 2022-07-22 19:23:53 -07:00
codegen termwiz: update nerdfont symbol data 2022-09-17 07:36:24 -07:00
data Respect emoji-variation-sequences.txt 2021-11-25 14:37:24 -07:00
examples termwiz: request xterm modifyOtherKeys 2022-09-21 21:07:10 -07:00
fuzz Add fuzzer for termwiz::escape::parser 2022-05-14 08:18:08 -07:00
src trim heap usage 2022-10-22 17:10:36 -07:00
Cargo.toml termwiz: fixup for 32-bit systems 2022-10-15 16:45:02 -07:00
CHANGELOG.md termwiz: request xterm modifyOtherKeys 2022-09-21 21:07:10 -07:00
LICENSE.md restructure termwiz tree prior to merging into wezterm repo 2018-08-05 07:55:30 -07:00
README.md termwiz: cut 0.9.0 release 2020-05-17 12:05:46 -07:00

Terminal Wizardry

This is a rust crate that provides a number of support functions for applications interested in either displaying data to a terminal or in building a terminal emulator.

It is currently in active development and subject to fairly wild sweeping changes.

Included functionality:

  • Surface models a terminal display and its component Cells
  • Terminal attributes are aware of modern features such as True Color, Hyperlinks and will also support sixel and iterm style terminal graphics display.
  • Surfaces include a log of Changes and an API for consuming and applying deltas. This is a powerful building block for synchronizing screen instances.
  • Escape sequence parser decodes inscrutable escape sequences and gives them semantic meaning, making the code that uses them clearer. The decoded escapes can be re-encoded, allowing applications to start with the semantic meaning and emit the appropriate escape sequence without embedding obscure binary bytes.
  • Capabilities allows probing for terminal capabilities that may not be included in the system terminfo database, and overriding them in an embedding application.
  • Terminal trait provides an abstraction over unix style ttys and Windows style console APIs. Changes from Surface can be rendered to Terminals. Terminals allow decoding mouse and keyboard inputs in both blocking or non-blocking mode.
  • Widget trait allows composition of UI elements at a higher level.
  • LineEditor implements shell-like line editing functionality.

Windows Support

Termwiz understands how to work with both the legacy console APIs and the new PTY and virtual terminal features available in Windows 10, allowing for true color terminal applications on Windows 10.

Documentation

https://docs.rs/termwiz