Autocomplete is slow

[feinstein]

When I type any code in IntelliJ IDEA, it becomes marked with red squiggly lines, then some 2 seconds later it will generate some autocomplete options, it gets kinda annoying.

I understand the Dart support was made with a Dart Analysis Server, so at each new key I press, there will be some sort of client-server communication.

I also understand why this architecture was chosen, it's the best way to make something quickly and for every platform out there.

But maybe we should start thinking how to move forward from this so the performance and tweaking for IntelliJ could be improved.

Maybe the Dart Analysis Server could be embedded into the Dart plug-in, bypassing the client-server communications? I am not familiar with the whole architecture, just trying to figure out how to improve performance.

[pq]

Thanks for the feedback.

@scheglov: what details would be useful for us to quantify the performance @feinstein is experiencing?

[scheglov]

1. How big is the file in which you type and get slow completions?
2. How many other libraries import this file, directly or indirectly?
3. How many libraries the file imports itself?
4. What is your operating system?
5. What version of Dart do you use?

[feinstein]

1. 10Kb, 300 lines
2. and 3.

import 'package:flutter/foundation.dart';
import 'package:flutter/services.dart';
import 'package:flutter/material.dart';
import 'package:flutter_svg/flutter_svg.dart';

import 'package:myproject/blocs/authentication_bloc.dart';
import 'package:myproject/configurations/assets.dart';

4. I am using a Dell Inspiron 13 7368 running Windows 10

Flutter 1.2.1 • channel stable • https://github.com/flutter/flutter.git Framework • revision 8661d8aecd (3 weeks ago) • 2019-02-14 19:19:53 -0800 Engine • revision 3757390fa4 Tools • Dart 2.1.2 (build 2.1.2-dev.0.0 0a7dcf17eb)

[scheglov]

1. 300 lines is not much, OK.
2. This does not answer my question. You listed flutter libraries, I doubt they import the file where you have performance problem with completions.
3. Again, I think there is misunderstanding. I asked which libraries the file imports.
4. Can you try to remove C:\Users\<your_name>\AppData\Local\.dartServer (this is the cache of Analysis Server, we had reports of performance problems with it on Windows, and think that they are fixed, but might worth to reset it). Then restart the server.

[feinstein]

Sorry, I didn't understand.

2. None.
3. This is the list of libraries the file imports at the beginning, isn't this what you asked for?

[scheglov]

2. This is weird. Then analysis and completions should be very fast.
3. Ah, OK. Yes, this is what I asked. Again, not too many libraries, should be fast.

We can try to log analysis activity in Analysis Server.

1. Triple-press Shift in IntelliJ.
2. Search for Registry...
3. Add to dart.server.additional.arguments: --new-analysis-driver-log=file:/Users/scheglov/tmp/444/analysis_driver.log
4. Restart Analysis Server.
5. Look in the file for suspiciously a lot of analysis or long time of analysis while you are completing.

[feinstein]

Ok, will do, thanks!

[bossbeagle1509]

Deleting the dart analysis server files as suggested by @scheglov immediately fixed the problem. Thanks !

[cyberpwnn]

I have to clean out these files every day or else im waiting literally 10 seconds for autocomplete to even show up. Idea locks up. I've have tons of disposable cores to do this work on, and plenty of memory to store all of those files on a ramdisk, why is this still a problem?

[ultimate-tester]

Just to keep this issue active, this is still a thing in 2022. Autocomplete and the context menu need at least 10 seconds (I keep bashing CTRL+ SPACE or ALT + ENTER until I get the results I expect to see) to work properly every time.

After using Flutter for a year, this is the stats of my .dartserver folder:

Deleting the entire .dartserver folder has unfortunately not solved this issue. I am experiencing the issue on my desktop with 16GB ram and 6 cores @ 3.60Ghz and consists of the following:

• Slow autocomplete
• Slow context menus
• Slow syntax highlighting
• On top of that, if I try context menu items like "replace child with children" or "add const modified" or any other menu item that would manipulate the code, 9 of of 10 times the new code ends up much higher in the file than where it's supposed to be causing a completely useless code.

Image portraying syntax highlighting issue

GIF showing the context menu issue

[AleksMx]

I have Core i9 with 16 CPU and 32 Gb RAM. After every 2-3 hot reloads, I get this picture for 3-4 seconds. In any project. Both in big ones and in hello world. The problem appeared a couple of months ago. It seems sometimes after a hot reload the analyzer starts re-analyzing all files in a project.

1. .dartServer folder I removed
2. Android Studio cache I cleaned