1774329 - Remove unneeded white spaces in JSON output

Status: RESOLVED FIXED

(Core :: Gecko Profiler, task, P2)

Description

[Gerald Squelart (he/him) (not at Mozilla since 2022-09-15)]

A possible quick win: Remove unneeded white spaces in JSON output. In particular, indents are currently adding a lot of characters!

Thank you Florian for finding out about this issue.

Comment 1

[Florian Quèze [:florian]]

Attachment: WIP patch

From what I remember, this mostly worked, but I had a few line breaks left (I think I had one every time a child process profile was joined to the parent profile), which got in the way of writing an automated test.

Comment 2

[Florian Quèze [:florian]]

Attachment: Previous attempt (also removed aStyle parameters)

This is my previous attempt, which was less finished, but I additionally tried to remove the aStyle parameters that became useless. I stopped and started over because I think removing useless parameters should be split out to a separate patch.

Comment 3

[Gerald Squelart (he/him) (not at Mozilla since 2022-09-15)]

Attachment: Bug 1774329 - Profiler gtests compute the proportion of JSON whitespace - r?florian

JSON whitespace comprises all spaces and newlines that are not inside strings,
and which could be removed without changing the decoded contents.

This tests the current state of affairs, where JSON whitespace in profiles may
account for up to 25% of the full length.

Comment 4

[Gerald Squelart (he/him) (not at Mozilla since 2022-09-15)]

Attachment: Bug 1774329 - JSONWriter() can be single-line from the top, removing the final newline - r?florian

Depends on D152601

Comment 5

[Gerald Squelart (he/him) (not at Mozilla since 2022-09-15)]

Attachment: Bug 1774329 - Make BaseProfileJSONWriter single-lined - r?florian

Depends on D152602

Comment 6

[Gerald Squelart (he/him) (not at Mozilla since 2022-09-15)]

Attachment: Bug 1774329 - Use single-line JSONWriters in nsProfiler functions - r?florian

Depends on D152603

Comment 7

[Gerald Squelart (he/him) (not at Mozilla since 2022-09-15)]

Attachment: Bug 1774329 - Remove whitespaces in gc stats' JSONPrinter - r?florian

Depends on D152604

Comment 8

[Gerald Squelart (he/him) (not at Mozilla since 2022-09-15)]

Attachment: Bug 1774329 - Output profiling logs in the most compact json - r?florian

Depends on D152605

Comment 9

[Gerald Squelart (he/him) (not at Mozilla since 2022-09-15)]

Attachment: Bug 1774329 - If SingleLineStyle is set at construction, also remove spaces after colons and commas - r?florian

These were the last remaining JSON whitespace characters, so we can now our
regression tests can check that there are non of these left.

Depends on D152606

Comment 10

[Gerald Squelart (he/him) (not at Mozilla since 2022-09-15)]

Attachment: Bug 1774329 - Remove now-ignored style parameters in ProfileJSONWriter functions - r?florian

Depends on D152607

Comment 11

[Gerald Squelart (he/him) (not at Mozilla since 2022-09-15)]

Attachment: Bug 1774329 - Remove JSONWriter style specifications from profiler code - r?florian

Depends on D152608

Comment 12

[Gerald Squelart (he/him) (not at Mozilla since 2022-09-15)]

Attachment: Bug 1774329 - Verify that there are no whitespaces in xpcshell/mochitest profiles - r?florian

As a bonus, this adds coverage of getProfileDataAsArrayBuffer().

Depends on D152609

Comment 13

[Gerald Squelart (he/him) (not at Mozilla since 2022-09-15)]

Attachment: Bug 1774329 - Rework shared test profiler controls - r?florian

Centralize calls to getProfileDataAsync to stop{,Now}AndGetProfile() in shared-head.js.

Depends on D152609

Comment 14

[Gerald Squelart (he/him) (not at Mozilla since 2022-09-15)]

Attachment: Bug 1774329 - Add minimal test for GC and CC markers - r?florian

This covers the gc stats' JSONPrinter changes, and would trigger the
verifyJSONStringIsCompact assertion (see next patch) without these changes.

Depends on D152843

Comment 15

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/182c7d6d14f3
Profiler gtests compute the proportion of JSON whitespace - r=florian
https://hg.mozilla.org/integration/autoland/rev/2b6e8a8a770b
JSONWriter() can be single-line from the top, removing the final newline - r=florian
https://hg.mozilla.org/integration/autoland/rev/66cc321b2ff6
Make BaseProfileJSONWriter single-lined - r=florian
https://hg.mozilla.org/integration/autoland/rev/e12a14c0e1a5
Use single-line JSONWriters in nsProfiler functions - r=florian
https://hg.mozilla.org/integration/autoland/rev/b3cfb0d05ed1
Remove whitespaces in gc stats' JSONPrinter - r=florian
https://hg.mozilla.org/integration/autoland/rev/25718fed7f54
Output profiling logs in the most compact json - r=florian
https://hg.mozilla.org/integration/autoland/rev/4fe98d466d30
If SingleLineStyle is set at construction, also remove spaces after colons and commas - r=florian
https://hg.mozilla.org/integration/autoland/rev/1c65183edd44
Remove now-ignored style parameters in ProfileJSONWriter functions - r=florian
https://hg.mozilla.org/integration/autoland/rev/8b166af41096
Remove JSONWriter style specifications from profiler code - r=florian
https://hg.mozilla.org/integration/autoland/rev/6f369c2cd337
Rework shared test profiler controls - r=florian
https://hg.mozilla.org/integration/autoland/rev/4870c2e16d49
Add minimal test for GC and CC markers - r=florian
https://hg.mozilla.org/integration/autoland/rev/bf26f05745aa
Verify that there are no whitespaces in xpcshell/mochitest profiles - r=florian

Comment 16

[Norisz Fay [:noriszfay]]

https://hg.mozilla.org/mozilla-central/rev/182c7d6d14f3
https://hg.mozilla.org/mozilla-central/rev/2b6e8a8a770b
https://hg.mozilla.org/mozilla-central/rev/66cc321b2ff6
https://hg.mozilla.org/mozilla-central/rev/e12a14c0e1a5
https://hg.mozilla.org/mozilla-central/rev/b3cfb0d05ed1
https://hg.mozilla.org/mozilla-central/rev/25718fed7f54
https://hg.mozilla.org/mozilla-central/rev/4fe98d466d30
https://hg.mozilla.org/mozilla-central/rev/1c65183edd44
https://hg.mozilla.org/mozilla-central/rev/8b166af41096
https://hg.mozilla.org/mozilla-central/rev/6f369c2cd337
https://hg.mozilla.org/mozilla-central/rev/4870c2e16d49
https://hg.mozilla.org/mozilla-central/rev/bf26f05745aa