After upgrading to Kubuntu 15.10 from 15.04, my workstation felt more buggy than ever. Aside from my previous post on the missing Dolphin context menus, some applications (Chrome, Firefox, Kate, Pidgin) would occassionally become unresponsive for several seconds. Additionally, my bluetooth mouse would also become unresponsive from time to time.
These issues were present in 15.04 and 14.10 as well, but it seemed to be happening more frequently in 15.10. My first solution to the problem was obviously calling Kubuntu 15.10 a pile of garbage and hoping future updates would alleviate the issues, but these occurrences obviously started negatively impacting my productivity in the office.
When looking at memory and CPU usage in top or ksysguard, I noticed Baloo at the top of the list. Actually, there were two processes, the primary Baloo process and its child file extractor. Memory usage was well over half a gigabyte, and CPU usage ranged from 10-50%. Baloo was the replacement for Nepomuk, the file indexing service introduced in KDE4.
I dislike the fact this is enabled by default. I've never had much use for file indexing, as I keep my files reasonably well organized and I know where everything is. Command line tools such as grep, find, and locate are my go-to tools for finding files, and typically more effective than firing up a GUI to find something.
But in all reality, on a high-end Intel Core i7 workstation with 16GB of RAM and a speedy SSD, I don't think its right that I should be seeing this resource usage from Baloo, not to mention the "disk sleep" messages I was seeing as well. I can only imagine how this would affect productivity on a lower-end Core i3 or even ARM device.
My solution? Disable it.
# balooctl disable
You can then kill the process in ksysguard or some the command line if its still running, or alternatively a reboot should do the trick as well if you're afraid of damaging your Baloo storage. I didn't particularly care, as I delete the Baloo files from my home directory after disabling the process.
Performance has increased exponentially, and I'm no longer seeing any of my applications or (bluetooth) processes temporarily becoming unresponsive.