Which Linux search/find tools to use while keeping minimal disk I/O?

[Fli]

On Debian 12 with KDE, there seems to be various file search options. But which one to use/allow indexing lets say 10 million files on a external USB drives, keeping minimum I/O impact and avoiding issues where the tool is unable to reach the external mountpoint or it is empty requiring wasteful re-indexing later?

A) locate
I am rarely using Linux "locate" default command (due to being CLI, so less convenient to work with - requiring more mouse/keyboard work), which can locate files very quickly by its file name.

Today the "sudo iotop-c -ao" shown a "find" to consume a lot of IO. Per what I have read here, it is ran daily defined in /etc/cron.daily/locate to be ran with lowest IO priority "IONICE_PRIORITY=7" and CPU nice priority "NICE=10".

That file also contains:

# paths which are pruned from updatedb database
PRUNEPATHS="/tmp /usr/tmp /var/tmp /afs /amd /alex /var/spool /sfs /media /var/lib/schroot/mount"

so maybe I can insert my external data drives paths to be removed from indexing in case I am not using "locate" CLI command and no GUI search frontend uses it? But maybe locate is the most I/O efficient file search utility and has a GUI front-end? I am unsure which is the best for my Debian 12+KDE, the ChatGPT told me that there are GUI search frontends:

1. Catfish: Catfish is a lightweight GTK+ search utility that can use locate as one of its search backends. It offers a simple interface and supports searching for files efficiently.
   (it did not use locate index. At Hamburger menu -> Refresh File Index... -> it shown that /var/lib/mlocate/mlocate.db was never updated. Updating took 6 hours! Searching seems to be significantly slower than FSearch )
2. Geany: While primarily an IDE, Geany includes a file search functionality that can utilize the locate command to find files quickly.
3. Gnome Search Tool: Part of the GNOME desktop environment, the Gnome Search Tool can also utilize locate to perform fast searches for files on the system.
4. KFind: This is a KDE application that provides a search functionality using locate among other methods. It's integrated into the KDE desktop environment and can perform quick searches.
5. Baloo: The file indexing and search framework used in KDE, Baloo can interface with locate to find files quickly. However, it primarily relies on its database to conduct searches.
6. MATE Search Tool: Similar to the Gnome Search Tool, the MATE Search Tool can use locate to search for files, particularly in distributions that use the MATE desktop environment.
7. Recoll: While primarily a full-text search tool, Recoll can also be configured to use locate for indexing files.

B) baloo
Then in my KDE I have enabled search (is it baloo?), app launcher menu, type "search", click "File search", enabled (incl. hidden). After like 48 hours of lagging system, it indexed like 10 million files (4,8GB index). I am unsure which GUI search frontends are good, I am now aware only about Krunner which is launched when you start typing at the desktop (when you minimize all windows using tray icon) or making Krunner appear using predefined keyb. shortcut (app launcher, search "shortcuts").

C) fsearch
I have been using fsearch GUI utility which is currently not working for me. Yet it returns results in a few seconds among millions of files (similar speed to "locate").