You both seem to ignore the fact that one can have projects where the plugin makes sense and others where it doesn't (work).
@techee In the instance I am describing here, the whole project directory is remote. The problem is not the indexing itself but the directory traversal which happens no matter what the index setting is AFAICT - and that it is done synchronously (apparently even in the UI thread). I don't use the plugin's sidebar BTW - I haven't even noticed that there is one till now. I am using the File Browser plugin for my file navigation needs - well that, search in files, and code navigation's and recently projectorganizer's lookup system but I'll take a look in the future.
@elextr Since there is no way to disable the plugin per project, ignoring the whole project tree is exactly what I am trying to achieve in the respective cases! Also, since neither documentation nor GUI indicates otherwise, I would argue that it is not at all obvious that the filter does not apply to the project's root directory. One could even argue that the filter should be applied to all the path components leading to the project's root IMHO. This would make effectively disabling the plugin based on the project's location even more generic (but since there is no customization for the plugin's default settings applying it to the rest of the path doesn't make too much sense in this regard).
I'd also be fine with an option to disable to plugin/directory traversal on a per project basis (although I actually think projectorganizer does lookups on just the open tabs even without the index from what I've seen in the code!). I am currently using the workaround of having the mountpoint as a subdirectory successfully and that's good enough for now.