At the time of this writing, this is not supported. See multi root support? #280. If you look at their projects page, that issue ticket is currently placed in the "Low priority" lane.
You can show your support for the issue ticket by giving a thumbs up reaction to the issue. But please don't make a "me too" comment. "me too" comments generally come off as annoying to repo maintainers because they clutter up discussion and don't contribute anything of significant value.
Some quotes from the discussion there:
lucywang000:
I noticed that python's pyright lsp only fires up one instance for multiple python projects, would it make sense to have a similar feature in clojure-lsp?
Some related quote from the doc (https://github.com/microsoft/pyright/blob/master/docs/configuration.md):
Multi-root workspaces (“Add Folder to Workspace…”) are supported, and each workspace root can have its own “pyrightconfig.json” file.
I used to open lots (5-10) of clojure/script projects, for e.g reading 3rdparty libs code. It doesn't make sense to have 10 lsp instances running and take up to 10-20GB of memory ...
ericdallo:
Yeah, it sound a good idea, but I'm not sure this works for most of clients, including lsp-mode
(lsp-clojure.el), it'd need some extra work on their side, and I'm no sure what need to be done on server side too
bpringe:
I was thinking about this recently. I think this is a good idea, though I know it might take some time and thought to implement well.
bpringe:
Another thing to consider is that if the memory usage of clojure-lsp can be drastically reduced via graalvm and other methods, this becomes less of a problem. I still think it's a worthwhile thing to do in any case, though.
Edit: Linking #229
snoe
I know some workplaces do multi repo/multi project/multi language stuff but it should be understood there's costs there, particularly around tooling support and it should be clear that those places should be investing in their tools.
I think that comparing ourselves to things like intellij or vscode backed by huge companies and hundreds of devs is a losing proposition.
So, in the end, my view is that collaboration and PRs can be welcome, but understand there's a high effort to maintain compatibility and performance and stability across servers and clients and to do the testing across those environments.