83df0afc4e
This change adds the flight recorder to the trace package. Flight recording is a technique in which trace data is kept in a circular buffer and can be flushed upon request. The implementation will be added in follow-up CLs. The flight recorder has already been implemented inside of the golang.org/x/exp/trace package. This copies the current implementation and modifies it to work within the runtime/trace package. The changes include: This adds the ability for multiple consumers (both the execution tracer and the flight recorder) to subscribe to tracing events. This change allows us to add multiple consumers without making major modifications to the runtime. Future optimizations are planned for this functionality. This removes the use of byte readers from the process that parses and processes the trace batches. This modifies the flight recorder to not parse out the trace clock frequency, since that requires knowledge of the format that's unfortunate to encode in yet another place. Right now, the trace clock frequency is considered stable for the lifetime of the program, so just grab it directly from the runtime. This change adds an in-band end-of-generation signal to the internal implementation of runtime.ReadTrace. The internal implementation is exported via linkname to runtime/trace, so the flight recorder can identify exactly when a generation has ended. This signal is also useful for ensuring that subscribers to runtime trace data always see complete generations, by starting or stopping data streaming only at generation boundaries. For #63185 Change-Id: I5c15345981a6bbe9764a3d623448237e983c64ec Reviewed-on: https://go-review.googlesource.com/c/go/+/673116 Auto-Submit: Michael Knyszek <mknyszek@google.com> Reviewed-by: Michael Knyszek <mknyszek@google.com> LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Release Notes
The initial and next subdirectories of this directory are for release notes.
For developers
Release notes should be added to next by editing existing files or creating
new files. Do not add RELNOTE=yes comments in CLs. Instead, add a file to
the CL (or ask the author to do so).
At the end of the development cycle, the files will be merged by being concatenated in sorted order by pathname. Files in the directory matching the glob "*stdlib/*minor" are treated specially. They should be in subdirectories corresponding to standard library package paths, and headings for those package paths will be generated automatically.
Files in this repo's api/next directory must have corresponding files in
doc/next/*stdlib/*minor.
The files should be in the subdirectory for the package with the new
API, and should be named after the issue number of the API proposal.
For example, if the directory 6-stdlib/99-minor is present,
then an api/next file with the line
pkg net/http, function F #12345
should have a corresponding file named doc/next/6-stdlib/99-minor/net/http/12345.md.
At a minimum, that file should contain either a full sentence or a TODO,
ideally referring to a person with the responsibility to complete the note.
If your CL addresses an accepted proposal, mention the proposal issue number in
your release note in the form /issue/NUMBER. A link to the issue in the text
will have this form (see below). If you don't want to mention the issue in the
text, add it as a comment:
<!-- go.dev/issue/12345 -->
If an accepted proposal is mentioned in a CL but not in the release notes, it will be flagged as a TODO by the automated tooling. That is true even for proposals that add API.
Use the following forms in your markdown:
[http.Request] # symbol documentation; auto-linked as in Go doc strings
[Request] # short form, for symbols in the package being documented
[net/http] # package link
[#12345](/issue/12345) # GitHub issues
[CL 6789](/cl/6789) # Gerrit changelists
To preview next content in merged form using a local instance of the website, run:
go run golang.org/x/website/cmd/golangorg@latest -goroot=..
Then open http://localhost:6060/doc/next. Refresh the page to see your latest edits.
For the release team
The relnote tool, at golang.org/x/build/cmd/relnote, operates on the files
in doc/next.
As a release cycle nears completion, run relnote todo to get a list of
unfinished release note work.
To prepare the release notes for a release, run relnote generate.
That will merge the .md files in next into a single file.
Atomically (as close to it as possible) add that file to _content/doc directory
of the website repository and remove the doc/next directory in this repository.
To begin the next release development cycle, populate the contents of next
with those of initial. From the repo root:
> cd doc
> cp -R initial/ next
Then edit next/1-intro.md to refer to the next version.