Commit 5d1b323. re-enabled the user presence updates and notifications.
Unfortunately, it showed poor performance due to the high frequency of bus
notifications triggered on our instance (~600k users).
In this rev., we don't trigger notifications on presence changes anymore, but
we rather send the presence of users we have a DM open with, at the end of each
poll period. For performance reasons, we ensure not to do that more than once
every 30 seconds.
We also refined the detection of the 'away' status client side. 'Last presence'
timestamps are stored in the local storage, and the current inactivity period
is sent at each poll. Those presence timestamps now rely on browser activity
detection (click, keypress... events) rather than on the focus on Odoo tabs.
Finally, we removed the no more necessary cron introduced in 5d1b323.
Aaron Bohy
f6c20fa4b3