Cyrus database and file usage data

[Thomas Jarosch]

Hi Bron,

Am 08.06.2016 um 08:22 schrieb Bron Gondwana via Cyrus-devel:
> *THE PLAN[tm]***
>  
> For JMAP support, I'm going to discard the existing conversations DB and
> create a sqlite database per user which contains everything of value. 

one thing to watch out for with sqlite:

It doesn't scale easily with multiple processes accessing the same DB.
The write-lock timeout is short by default and a "modifying"
query might error out.

If this per-user DB will be used by multiple processes
(think multiple JMAP connection in parallel from a web frontend)
+ LMTP delivery at the same time, this might occur sooner or later.

I've learned about this issue the hard way with a central sqlite DB
for ActiveSync device management on our horde installation.

Related topic:
http://beets.io/blog/sqlite-nightmare.html

Cheers,
Thomas