1846781 - Use recalc_frecency for origins frecency instead of updating in triggers

Status: RESOLVED FIXED

(Toolkit :: Places, task, P3)

Description

[Marco Bonardo [:mak]]

While this will be a bit less performant than the old system updating the score by adding/subtracting in a trigger, it prepares us to take future algorithms that are not just a sum/subtraction, and it's less error-prone.

Comment 1

[Marco Bonardo [:mak]]

Attachment: Bug 1846781 - Use recalc_frecency for updating origins frecency instead of triggers. r=daisuke

So far we updated origins frecency in SQL triggers. While this guarantees good
performance, it has some downsides:

• using different algorithms is complicate, the current system only works
  with a straight sum of page frecencies. We are planning to experiment and
  eventually graduate new algorithms in the future.
• it requires using multiple temp tables and DELETE triggers, that is quite
  error prone for consumers, they may forget to DELETE from the temp tables
  breaking data coherency.
• there's not much ATOMicity, since the origins update must be triggered apart
  and a crash would lost the requested changed

This patch is changing the behavior to be closer to the recalc_frecency one that
is used for pages. When pages are added or removed, recalc_frecency of its
origin is set to 1. Later frecencies will be recalculated in chunks.
While this is a bit less efficient than the existing system, it solves all the
problems presented above.
A threshold is recalculated at each chunk, and stored in the moz_meta table.
Temporarily the old STATS are also set in the moz_meta table, to allow for
downgrades. Those can be removed a couple versions in the future.

The after delete temp table is maintained because there's no more efficient way
to remove orphan origins promptly. Thus after removals from moz_places consumers
MUST DELETE from the temp table, otherwise orphan origins may remain. We'll
introduce some maintenance task to remove those, anyway, for privacy reasons.

Comment 2

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/3020232880d7
Use recalc_frecency for updating origins frecency instead of triggers. r=daisuke

Comment 3

[Cosmin Sabou [:CosminS]]

https://hg.mozilla.org/mozilla-central/rev/3020232880d7

Comment 4

[Julian Descottes [:jdescottes]]

I see a console.log landed here at https://searchfox.org/mozilla-central/rev/b741ddde6c678ca7025858952202d20664491555/toolkit/components/places/PlacesUtils.sys.mjs#2266

Looks like a leftover, should it be removed?

Comment 5

[Marco Bonardo [:mak]]

(In reply to Julian Descottes [:jdescottes] from comment #4)

I see a console.log landed here at https://searchfox.org/mozilla-central/rev/b741ddde6c678ca7025858952202d20664491555/toolkit/components/places/PlacesUtils.sys.mjs#2266

Looks like a leftover, should it be removed?

oops, yes thank you.
I'll add a revision to remove it.

Comment 6

[Marco Bonardo [:mak]]

Attachment: Bug 1846781 - remove leftover console.log

Comment 7

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/3a58c7fc0959
remove leftover console.log r=places-reviewers,Standard8

Comment 8

[Iulian Moraru]

https://hg.mozilla.org/mozilla-central/rev/3a58c7fc0959