I have 3 years old ThinkPad P71 laptop, with 3840x2160 display. Have Fedora 33 installed. I've faced persistent issues with typing lag with all versions of RStudio that I tried, at the moment latest version provided by my distribution is 1.3.1093, and I just tried with 1.4.1087 preview version downloaded from rstudio.com.
I tried all the suggestion that I found on net, in particular with disabling diagnostics, and trying different rendering engines, to no avail. The typing lag is always there, oftentimes it takes couple seconds between typing something and then seeing it in the console. The processor activity also get rather high whenever I do something in RStudio, fans start working very soon. The only help is to decrease size of RStudio window, say to about 1500x1000 and below, but then even if my screen is 17", this is just quarter of the screen and pretty much unusable. Also, when plain R run from a terminal, it's very responsive, so it's definitely something about GUI.
Can someone shed the light about how RStudio is actually doing on-screen rendering, and is there anything else here to try? I have some background in computer graphics, and I really can't understand that rendering text could still, in late 2020, be a problem. Any other scientific IDE that I tried, like Matlab or IntelliJ with R plugin or Juno etc., works fine on my laptop.
This could be related to the console getting very slow when there is a large amount of data displayed in the console. One way to resolve the problem is to clear the console (broom icon top left of console). Another is to try the new feature via Preferences->Console, enable "Limit console display to a subset of total content". This is off by default in 1.4 as it is still in development, with a few known display issues we are working on.
Another possible reason for the slowdown: are you using a network directory / NFS mount for shared information? Is this with Desktop, or RStudio Server?
The rendering itself is done via an embedded Chromium browser, via QtWebEngine's wrapper.
Experiment with different settings under Tools / Global Options / General / Advanced / Rendering Engine, and see if one of those gives you better results.
The problem is with Desktop version. I'm not using any kind of network drive, running from local and fast NVMe disk. The problem is not with the amount of data displayed on console, it appears as soon as I open RStudio, or after I clear the console. The "Limit console display to a subset of total content" option doesn't seem to help.
I already tried all the options for the rendering engine, as well as under General/Graphics in 1.4 version, I don't see much of the difference.
Let me also mention that, as my laptop has both NVIDIA and Intel graphics, I tried with both, using NVIDIA proprietary driver and then Intel driver, again to not much difference.
Admittedly, I don't have previous experiences with IDEs/editors based on Chromium, like Atom etc. However, I can confirm that some other such applications, like Slack, are very problematic too on my HiDPI screen, so that pretty much explains it.
Anyway, thanks again for your help. I guess I'll try to live with smaller RStudio window, and hope for improvements in the future (version 1.4 indeed works slightly better).