alacritty: Slower redraw with bigger window

After having a great start with Alacritty, I realized today, that the redraw time increases significantly when the window is bigger. It works “okay” on my Retina display, but when I’ve tried to use it today on my 4K screen in the office, I’ve noticed this slow down. I’m using a 15 inch MacBook Pro from 2015.

I made two Gifs that shows this issue with the render_timer turned on.

Small

Full Screen

System

OS: macOS (10.15.5) Version: alacritty 0.4.3 (c723247)

Logs

The last line shows the full screen size.

> alacritty -vv
Created log file at "/var/folders/2r/xknybh5n1yjcz3kg_7pk44c00000gn/T/Alacritty-46241.log"
[2020-06-15 20:57:43.565647000] [DEBUG] Using environment locale: en_US.UTF-8
[2020-06-15 20:57:43.565883000] [INFO] Welcome to Alacritty
[2020-06-15 20:57:43.565914000] [INFO] Configuration loaded from "/Users/danieltrautmann/.config/alacritty/alacritty.yml"
[2020-06-15 20:57:43.608875000] [DEBUG] Estimated DPR: 2
[2020-06-15 20:57:43.608957000] [DEBUG] Estimated Cell Size: 15 x 40
[2020-06-15 20:57:43.608986000] [DEBUG] Estimated Dimensions: None
[2020-06-15 20:57:43.673661000] [INFO] Device pixel ratio: 2
[2020-06-15 20:57:43.677113000] [INFO] Initializing glyph cache...
[2020-06-15 20:57:43.720220000] [INFO] ... finished initializing glyph cache in 0.043018491s
[2020-06-15 20:57:43.720329000] [INFO] Cell Size: 15 x 40
[2020-06-15 20:57:43.720360000] [INFO] Padding: 10 x 10
[2020-06-15 20:57:43.720387000] [INFO] Width: 1600, Height: 1200
[2020-06-15 20:57:43.720523000] [INFO] PTY Dimensions: Line(29) x Column(105)
[2020-06-15 20:57:43.724023000] [INFO] Initialisation complete
[2020-06-15 20:58:15.895569000] [DEBUG] New num_cols is 190 and num_lines is 42
[2020-06-15 20:58:15.905335000] [INFO] Width: 2880, Height: 1710