Documentation and completions slow to appear after startup

[r-zip]

FYI, I have had this problem with Emacs 26.2, Emacs 26.3, and Emacs 27.0.50 built with jansson.

After the language server has started, documentation and completion candidates are slow to appear, and I get lots of "task cancelled" messages.

By contrast, VSCode is quick to provide completions and documentation after startup.

Since we know that the VSCode and Emacs servers are the same, do we know what difference between the clients is causing this issue?

[yyoncho]

@r-zip I have investigated that in the past. Task cancelled is received if there are changes in the files that the language server is scanning right now. In that particular case the issue was caused by the emacs backup files.

[r-zip]

@yyoncho I just disabled backups completely and set create-lockfiles to nil. Still having the issue. Do you have any other recommendations?

[yyoncho]

@r-zip I debugged it in the past by recompiling the csharp langauge server with additional logging. If you can provide a project to reproduce the issue with(ideally using the docker image - you may use https://github.com/emacs-lsp/lsp-docker ) I could take a look. Without a reproducer, it will be really hard to do anything on our side.

[seagle0128]

mspyls takes long time to index and cache at the first startup, then it's faster. I observed the same behaviors in VSCode.