Comment by scratcheee | Hacker News Reader

Comment by scratcheee | Hacker News Reader

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They explained that in the retrospective.

The code _does_ work the way you describe, _except_ for the latent bug that caused the networking thread to get stuck in an infinite loop, which it was never supposed to do, even when errors occur.

It was never supposed to work that way, and the fact it did was because of a bug they'd never seen before.

So it wasn't that "oops, we shouldn't have built the system to get stuck forever when it fails" but rather "this bug triggered that bug which combined to cause a far worse result than 1 bug alone could have".

The only "lesson learnt" there is either that they need better ways to find bugs, quadruple up their thread count just so that different subsystems can't coexist on the same threads to avoid a theoretical problem that shouldn't ever happen again, or they just come up with infrastructural changes to minimise the negative results of the next "2 bugs reacted together and caught fire" scenario, which is the one they went with, and the only sane one.

Or they could reduce complexity by not adding things like telemetry, which has no direct user benefit and therefore should not be included in release versions. There should be no service that all firefox installs connect to.

Telemetry has massive direct user benefit. It gives every user a vote on how important each feature is rather than letting power users who manually submit feedback control the show.

Incorrect. It gives the designers and developers an opaque dataset of user behavior which they can interpret in many ways. I find their interpretations of this data to be highly motivated and suspect.

How does gradually removing power user features over time empower regular users over time?

Hint: It doesn't.

And then when the regular users are all piling up on support because they can't learn how to configure the product (or indeed ask their power user friends for help, since the features no longer exist), what happens then?

Nothing. Nothing happens then. And the shitshow continues.

Even ignoring that decisions based on Telemetry are very much influenced by the person making the decision, importance has nothing to do with how much a feature is used.

That is not what telemetry does. Useful features that are hidden aren't distinguished from useless features people don't use. Features that are used rarely but are super important aren't distinguished from features that don't work well.

Feature usage is a poor proxy for usefulness, importance, usability, visibility; it confounds them all.

> Telemetry has massive direct user benefit.

No. The benefit you're describing is not a direct benefit. It's an exemplary instance of indirect benefit even under the most generous evaluation criteria/process.

Has it in truth done that?

I know of changes for the worse that Mozilla has made, using telemetry as a justification.

I don't know if I've heard of any changes for the better that have been prompted by telemetry data. It could be... maybe there are bug fixes or UI refinements. I just haven't heard of any.

Some examples of things I've used telemetry for at Mozilla:

* Noticed performance regressions not caught by our testing, and therefore been able to fix the regression.

* Noticed an unexpected number of users with hardware acceleration disabled, and therefore been able to find and fix the bug that was causing them to have acceleration switched off

* Figure out which device in a category is most commonly used by our users, so that I can dogfood my work on a representative device

Those are just a few examples off of the top of my head. It's not about removing features because telemetry says nobody uses them. People Mozilla use telemetry to answer all sorts of important questions. We also have to jump through hoops to add any new data collection, justifying why it's needed and ensuring the data is not personal. As is right, because we take user privacy very seriously

Telemetry is what allows Mozilla to quickly know if e.g. a particular hardware combination is causing lots of failures for lots of people, and to act on that if it happens. That seems to me to be a clear user benefit.

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