While the overall design of Baloo seems quite elaborated and well done, it uses almost any possible kernel feature already to reduce its priority, but still there are some issues how it is negatively impacting real world configurations in the wild.
This task should track some of the observed issues and help understanding it:
- IO thrashing in low-mem situations D24540
- Re-indexing files on every reboot, probably due to unstable DocId? May affect only some filesystems (e.g., btrfs) [BUG:404057](https://bugs.kde.org/show_bug.cgi?id=404057)
- Kernel memory management overhead due to huge mmap and IO behavior (but there's no real way around it currently) D24540
- High-impact transaction behavior (40 files/trx may have a high memory overhead while less files/trx increase the fsync/fdatasync overhead), a more dynamic handling could fix this
- Database design issues (that's always a difficult balance between DB size, lookup latency, and memory usage at both index time and search time)
- General memory overhead or leaks which can accumulate over time and cause crashes D24502
Discussion of the individual problems already exists in some other tasks or changesets which can be linked here.
New ideas can be added to the list above and followed up in individual threads.