897074 - getAutoCompleteResults sometimes issues extremely long SQL queries

Status: RESOLVED FIXED

(Toolkit :: Form Manager, defect)

Description

[Vladan Djeric (:vladan)]

Attachment: Examples of very long SQL statements

The frecency calculation query in FormHistory.jsm can sometimes be over 1 million characters long! This is bad for performance and also bloats Telemetry pings (bug 896737).

Comment 1

[Matthew N. [:MattN]]

We can probably bail from both loops over search tokens once we're over some threshold:
for (let i = 0; i < searchTokens.length; i++) {

I suspect these are mostly caused by users pasting long text into single-line text fields.

Comment 2

[Matthew N. [:MattN]]

Attachment: v.1 Cap to 30 tokens when querying the database

This should reduce the telemetry spam and probably help performance for long texts (maybe accidental pastes) while still preserving the accuracy when we re-use previous results.

Comment 3

[Justin Dolske [:Dolske]]

Comment on attachment 8344118 [details] [diff] [review]
v.1 Cap to 30 tokens when querying the database

Review of attachment 8344118 [details] [diff] [review]:
-----------------------------------------------------------------

Suggestion: I'd tend to think a much lower value (5? or even 10?) would be plenty.

Comment 4

[Matthew N. [:MattN]]

(In reply to Justin Dolske [:Dolske] from comment #3)
> Comment on attachment 8344118 [details] [diff] [review]
> v.1 Cap to 30 tokens when querying the database
> 
> Suggestion: I'd tend to think a much lower value (5? or even 10?) would be
> plenty.

Sorry, I started changing this and then got distracted by other bugs and pushed this without lowering it. I pushed a follow-up to lower to 10.

https://hg.mozilla.org/integration/fx-team/rev/c62c26e3c73f
https://hg.mozilla.org/integration/fx-team/rev/1c7402403124

Comment 5

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/mozilla-central/rev/c62c26e3c73f
https://hg.mozilla.org/mozilla-central/rev/1c7402403124