Pre-initialize project import (warm LS)?

[guw]

Did anyone experiment with pre-initializing the project import?

Our import takes a couple minutes and we are looking for a way to pre-initialize the workspace in a background (headless) process. Thus, when the user brings up VS Code, the Java extension would activate much faster as it already has a workspace populated with Java projects.

[rgrunber]

Have you tried with with setting "java.autobuild.enabled": "false" ? I think the part that often takes longest in the project import is the build (which by default happens automatically).

I would think that if the contents of the workspace storage are in place, that ultimately reduces the import time also. Those contents are stored in VS Code's data directory, under User/workspaceStorage/${projectFolderID}, where ${projectFolderID} (at least on Linux) is the md5 checksum of the folder's inode number, appended to its absolute path (eg. ${folder_path}${inode}). You can also just check the workspace.json file inside each folder ID for the absolute folder path associated with it. Under redhat.java/jdt_ws, you'll find that it's basically the workspace's state location (.metadata/) that ends up having most of the important data. If that directory were shared, it might be enough to reduce the import time, but I haven't really played with this idea.

There has been work done to reduce indexing through things like java.sharedIndexes.enabled, but that doesn't drastically improve the time so it happens in the background.

Update: Another thing is that the first time one launches a new version of vscode-java, there are a lot of files that get cached into User/globalStorage/redhat.java/${version}/config_*. All of the jars that are nested into OSGi bundles need to get cached there to be referenced (eg. think Bundle-ClassPath), as well as any wiring instructions that may have taken time to compute on the initial startup.

[guw]

No. I do not want to disable auto building. I really want to "pre-import" projects. Our import is specifically expensive.