duchain cache directories

[René J.V. Bertin]

On Sunday November 20 2016 22:00:46 Milian Wolff wrote:

> The cache is not cross-process safe, thus it must be per-session.

None of it is cross-process safe (there are lots of files in a cache dir), and would using locks incur too large a penalty under real-world circumstances where it may be unlikely that different sessions attempt to write the same cache items at the same time?

> AFAIR Milian evaluated that a while ago, and it turned out to be way too
> slow for what we need to do with it.

Hmm, but it might help with the cross-process issue, no?
It's probably very true that getting the performance right will require some serious experience with db tuning, and maybe something a little more "professional" than sqlite3. 

For reference, I just did a bit of periodic cache cleanup:
- remove all those tiny ~/.cache/kdevduchain/*/topcontexts files
- HFS compression (zip level 8) which crunched the disk space usage by a factor 10


R.