Reducing data latency: accelerating the 'shutdown' main ping

Alessio Placitelli aplacitelli at
Mon May 22 14:03:27 UTC 2017

The 'main-ping
contains the bulk of our probes and measurements.
The 'main-ping' with reason 'shutdown' makes up for about 80% of all the
main pings <>.

Thanks to Ping Sender
we are receiving most of them within minutes from the browser shutdown.

*How did we do it?*
Starting from the second browsing session, when the browser shuts down, we
spawn a separate process (Ping Sender!) with the sole responsibility of
transmitting the 'shutdown' main-ping, instead of waiting for the browser
to be restarted by the user.

The analysis
of the data coming from Nightly looks very promising: 85% of the 'shutdown'
pings are received as soon as generated, versus 35% within the first hour
when no pingsender is used.

*Why are we starting from the second session?*
To prevent 'bot-profiles'/'bot-machines' just creating a single profile and
then deleting it after the first session to skew our analyses.

*Is it complete?*
This feature is functionally complete, we're in the process of smoothing
some rough edges, and have bugs filed for that (on track for 55).

- Bug 1363345: Don't use the pingsender when Firefox closes because the OS
is shutting down
- Bug 1364673: Unwanted mouse throbber appears a few seconds after exiting
Nightly when telemetry is enabled
- Bug 1365978: Validate sending shutdown pings using the PingSender [Beta]

If anything seems off and you think it's due to the pingsender, please file
a bug against 1343277.

Kudos to everyone involved in this!

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <>

More information about the fhr-dev mailing list