gecko-dev/taskcluster/docs
Andrew Halberstadt 4c371dd4d8 Bug 1884364 - Create a new 'files_changed' parameter, r=taskgraph-reviewers,releng-reviewers,jcristau
We use hg.m.o's `json-automationrelevance` endpoint for a variety of reasons
such as getting the files changed for optimization purposes, or finding the
base revision for diff purposes. But this endpoint is slow and puts undue load
on hg.mozilla.org if queried too often.

The helper function that fetches this is memoized, so in theory we should only
ever make this request once per graph generation. However, there are still cases
where we request this unnecessarily:

1. When running `./mach taskgraph` locally, we first fetch
`json-automationrelevance` and then fall back to fetching it locally if the
revision wasn't found. I believe the reason for this is to be able to generate
identical graphs as produced by CI.

2. When specifying multiple parameters (so graphs are generated in parallel),
the memoize won't cache across processes, so we make the request once per
parameter set.

3. Any other time we generate tasks outside the context of a Decision task (e.g
`./mach try`), as there are transforms that call this function.

By turning `files_changed` into a parameter, we can ensure that this value gets
"frozen" by the Decision task and it will never need to be recomputed. E.g, you
could use `-p task-id=<decision id>` and you'd still get the `files_changed`
value that Decision task computed. This means, that for all non-Decision use
cases we can rely on local VCS to give us our changed files.

This should greatly cut back on the number of queries being made to `hg.m.o`.

Differential Revision: https://phabricator.services.mozilla.com/D204127
2024-03-19 14:13:54 +00:00
..
howto
img
kinds
optimization
transforms Bug 1824856 - update documentation with task kinds/attributes and new run-using values coming from firefox-android. r=bhearsum,releng-reviewers 2023-07-17 17:12:32 +02:00
attributes.rst Bug 1877823 - add simple descriptions for new items in attributes.rst. r=gabriel,releng-reviewers 2024-01-31 15:19:50 -07:00
balrog.rst
caches.rst
config.rst
cron.rst
index.rst
kinds.rst Bug 1824856 - migrate release-notify-testrail kind from firefox-android. r=gbrown,owlish,releng-reviewers,geckoview-reviewers,jajohnson 2024-02-12 14:35:56 +01:00
parameters.rst Bug 1884364 - Create a new 'files_changed' parameter, r=taskgraph-reviewers,releng-reviewers,jcristau 2024-03-19 14:13:54 +00:00
partials.rst
partner-attribution.rst
partner-repacks.rst
platforms.rst
reference.rst
release-promotion-action.rst
release-promotion.rst
signing.rst
taskgraph.rst
try.rst
using-the-mozilla-source-server.rst
versioncontrol.rst