1463099 - Compress GeckoView persistence files

Status: RESOLVED WONTFIX

(Toolkit :: Telemetry, enhancement, P3)

Description

[Alessio Placitelli [:Dexter]]

Persisted probe files for GeckoView can eat up to 400kB in total. We should consider compressing when saving them to the disk.

Moreover, we should evaluate the performance impact of doing so compared to the disk space wins.

One other possibility could be to use a sparse histogram count representation vs a dense one:

> [(3, 3), ...]

vs

> [0, 0, 3, ...]

Comment 1

[Chris H-C :chutten]

We use sparse counts following this algorithm in TelemetrySession: https://searchfox.org/mozilla-central/rev/2aa42f2cab4a110edf21dd7281ac23a1ea8901f9/toolkit/components/telemetry/TelemetrySession.jsm#831

Not sure if it fits the bill or not, but it's a format we already have.

Comment 2

[Chris H-C :chutten]

Given the new GV Streaming Telemetry approach in bug 1566340 and the deprecation of non-Glean-SDK methods of data collection in mobile products, this work isn't going to happen.

If you're interested or concerned about this, please get in touch with us on IRC#telemetry or Slack#fx-metrics to have a chat about what this means specifically for you.