golang
net: enable multipath TCP by default for listeners
A previous change [1] was introduced to enable MPTCP by default for both the clients and servers, based on the discussions [2] in golang#56539, where MPTCP would be an opt-in for a release or two, and then would become an opt-out.
This change was not accepted at the time because the support for a few socket options was missing [3]. Now that this support has been added [4] and backported to stable versions not to block MPTCP deployment with Go, it sounds like a good time to reconsider the use of MPTCP by default.
Instead of enabling MPTCP on both ends by default, as a first step, it seems safer to change the default behaviour only for the server side (Listeners). On the server side, the impact is minimal: when clients don't request to use MPTCP, server applications will create "plain" TCP sockets within the kernel when connections are accepted, making the performance impact minimal. This should also ease experiments where MPTCP is enabled by default on the client side (Dialer).
The changes in this patch consist of a duplication of the mptcpStatus enumeration to have both a mptcpStatusDial and a mptcpStatusListen, where MPTCP is enabled by default in mptcpStatusListen, but disabled by default in mptcpStatusDial. It is still possible to turn MPTCP support on and off by using GODEBUG=multipathtcp=1.
[1] https://go-review.googlesource.com/c/go/+/563575 [2] https://go.dev/issue/56539#issuecomment-1309294637 [3] https://github.com/multipath-tcp/mptcp_net-next/issues/383 [4] https://github.com/torvalds/linux/commit/bd11dc4fb969ec148e50cd87f88a78246dbc4d0b [5] https://www.mptcp.dev/faq.html#why--when-should-mptcp-be-enabled-by-default
Updates #56539
This PR (HEAD: f74c324a5107c93d6091636ef5230f4132e3dd99) has been imported to Gerrit for code review.
Please visit Gerrit at https://go-review.googlesource.com/c/go/+/607715.
Important tips:
- Don't comment on this PR. All discussion takes place in Gerrit.
- You need a Gmail or other Google account to log in to Gerrit.
- To change your code in response to feedback:
- Push a new commit to the branch used by your GitHub PR.
- A new "patch set" will then appear in Gerrit.
- Respond to each comment by marking as Done in Gerrit if implemented as suggested. You can alternatively write a reply.
- Critical: you must click the blue Reply button near the top to publish your Gerrit responses.
- Multiple commits in the PR will be squashed by GerritBot.
- The title and description of the GitHub PR are used to construct the final commit message.
- Edit these as needed via the GitHub web interface (not via Gerrit or git).
- You should word wrap the PR description at ~76 characters unless you need longer lines (e.g., for tables or URLs).
- See the Sending a change via GitHub and Reviews sections of the Contribution Guide as well as the FAQ for details.
Message from Gopher Robot:
Patch Set 1:
Congratulations on opening your first change. Thank you for your contribution!
Next steps: A maintainer will review your change and provide feedback. See https://go.dev/doc/contribute#review for more info and tips to get your patch through code review.
Most changes in the Go project go through a few rounds of revision. This can be surprising to people new to the project. The careful, iterative review process is our way of helping mentor contributors and ensuring that their contributions have a lasting impact.
During May-July and Nov-Jan the Go project is in a code freeze, during which little code gets reviewed or merged. If a reviewer responds with a comment like R=go1.11 or adds a tag like "wait-release", it means that this CL will be reviewed as part of the next development cycle. See https://go.dev/s/release for more details.
Please don’t reply on this GitHub thread. Visit golang.org/cl/607715. After addressing review feedback, remember to publish your drafts!
Message from Matthieu Baerts:
Patch Set 2: Code-Review+1
(1 comment)
Please don’t reply on this GitHub thread. Visit golang.org/cl/607715. After addressing review feedback, remember to publish your drafts!
Message from komu wairagu:
Patch Set 3:
(1 comment)
Please don’t reply on this GitHub thread. Visit golang.org/cl/607715. After addressing review feedback, remember to publish your drafts!
Message from Matthieu Baerts:
Patch Set 3: Code-Review+1
(1 comment)
Please don’t reply on this GitHub thread. Visit golang.org/cl/607715. After addressing review feedback, remember to publish your drafts!
Message from Ian Lance Taylor:
Patch Set 3:
(2 comments)
Please don’t reply on this GitHub thread. Visit golang.org/cl/607715. After addressing review feedback, remember to publish your drafts!
Message from Aperence Ark:
Patch Set 3:
(2 comments)
Please don’t reply on this GitHub thread. Visit golang.org/cl/607715. After addressing review feedback, remember to publish your drafts!
Message from Ian Lance Taylor:
Patch Set 3:
(1 comment)
Please don’t reply on this GitHub thread. Visit golang.org/cl/607715. After addressing review feedback, remember to publish your drafts!
Message from Matthieu Baerts:
Patch Set 3:
(1 comment)
Please don’t reply on this GitHub thread. Visit golang.org/cl/607715. After addressing review feedback, remember to publish your drafts!
Message from Aperence Ark:
Patch Set 3:
(1 comment)
Please don’t reply on this GitHub thread. Visit golang.org/cl/607715. After addressing review feedback, remember to publish your drafts!
Message from Ian Lance Taylor:
Patch Set 3:
(1 comment)
Please don’t reply on this GitHub thread. Visit golang.org/cl/607715. After addressing review feedback, remember to publish your drafts!
This PR (HEAD: 6e9cccc5bf40ce261f05cd2630a612ca7c114c60) has been imported to Gerrit for code review.
Please visit Gerrit at https://go-review.googlesource.com/c/go/+/607715.
Important tips:
- Don't comment on this PR. All discussion takes place in Gerrit.
- You need a Gmail or other Google account to log in to Gerrit.
- To change your code in response to feedback:
- Push a new commit to the branch used by your GitHub PR.
- A new "patch set" will then appear in Gerrit.
- Respond to each comment by marking as Done in Gerrit if implemented as suggested. You can alternatively write a reply.
- Critical: you must click the blue Reply button near the top to publish your Gerrit responses.
- Multiple commits in the PR will be squashed by GerritBot.
- The title and description of the GitHub PR are used to construct the final commit message.
- Edit these as needed via the GitHub web interface (not via Gerrit or git).
- You should word wrap the PR description at ~76 characters unless you need longer lines (e.g., for tables or URLs).
- See the Sending a change via GitHub and Reviews sections of the Contribution Guide as well as the FAQ for details.
Message from Aperence Ark:
Patch Set 3:
(1 comment)
Please don’t reply on this GitHub thread. Visit golang.org/cl/607715. After addressing review feedback, remember to publish your drafts!
This PR (HEAD: 201b763c5dac8798139cc1d26f5a3f2f9e65b774) has been imported to Gerrit for code review.
Please visit Gerrit at https://go-review.googlesource.com/c/go/+/607715.
Important tips:
- Don't comment on this PR. All discussion takes place in Gerrit.
- You need a Gmail or other Google account to log in to Gerrit.
- To change your code in response to feedback:
- Push a new commit to the branch used by your GitHub PR.
- A new "patch set" will then appear in Gerrit.
- Respond to each comment by marking as Done in Gerrit if implemented as suggested. You can alternatively write a reply.
- Critical: you must click the blue Reply button near the top to publish your Gerrit responses.
- Multiple commits in the PR will be squashed by GerritBot.
- The title and description of the GitHub PR are used to construct the final commit message.
- Edit these as needed via the GitHub web interface (not via Gerrit or git).
- You should word wrap the PR description at ~76 characters unless you need longer lines (e.g., for tables or URLs).
- See the Sending a change via GitHub and Reviews sections of the Contribution Guide as well as the FAQ for details.
Message from Matthieu Baerts:
Patch Set 5: -Code-Review
(7 comments)
Please don’t reply on this GitHub thread. Visit golang.org/cl/607715. After addressing review feedback, remember to publish your drafts!
Message from Aperence Ark:
Patch Set 5:
(6 comments)
Please don’t reply on this GitHub thread. Visit golang.org/cl/607715. After addressing review feedback, remember to publish your drafts!
Message from Aperence Ark:
Patch Set 5:
(1 comment)
Please don’t reply on this GitHub thread. Visit golang.org/cl/607715. After addressing review feedback, remember to publish your drafts!
Message from Matthieu Baerts:
Patch Set 5:
(1 comment)
Please don’t reply on this GitHub thread. Visit golang.org/cl/607715. After addressing review feedback, remember to publish your drafts!
Message from Aperence Ark:
Patch Set 5:
(1 comment)
Please don’t reply on this GitHub thread. Visit golang.org/cl/607715. After addressing review feedback, remember to publish your drafts!
This PR (HEAD: a77f77be04e76914e78c9ddd04cb4145a8e7e95d) has been imported to Gerrit for code review.
Please visit Gerrit at https://go-review.googlesource.com/c/go/+/607715.
Important tips:
- Don't comment on this PR. All discussion takes place in Gerrit.
- You need a Gmail or other Google account to log in to Gerrit.
- To change your code in response to feedback:
- Push a new commit to the branch used by your GitHub PR.
- A new "patch set" will then appear in Gerrit.
- Respond to each comment by marking as Done in Gerrit if implemented as suggested. You can alternatively write a reply.
- Critical: you must click the blue Reply button near the top to publish your Gerrit responses.
- Multiple commits in the PR will be squashed by GerritBot.
- The title and description of the GitHub PR are used to construct the final commit message.
- Edit these as needed via the GitHub web interface (not via Gerrit or git).
- You should word wrap the PR description at ~76 characters unless you need longer lines (e.g., for tables or URLs).
- See the Sending a change via GitHub and Reviews sections of the Contribution Guide as well as the FAQ for details.
Message from Aperence Ark:
Patch Set 6:
(1 comment)
Please don’t reply on this GitHub thread. Visit golang.org/cl/607715. After addressing review feedback, remember to publish your drafts!
Message from Matthieu Baerts:
Patch Set 6: Code-Review+1
(1 comment)
Please don’t reply on this GitHub thread. Visit golang.org/cl/607715. After addressing review feedback, remember to publish your drafts!
Message from Ian Lance Taylor:
Patch Set 6: Commit-Queue+1
(2 comments)
Please don’t reply on this GitHub thread. Visit golang.org/cl/607715. After addressing review feedback, remember to publish your drafts!
Message from Go LUCI:
Patch Set 6:
Dry run: CV is trying the patch.
Bot data: {"action":"start","triggered_at":"2024-08-27T17:56:58Z","revision":"02c12ba512b368151c023098a3b9595782dd36ea"}
Please don’t reply on this GitHub thread. Visit golang.org/cl/607715. After addressing review feedback, remember to publish your drafts!
Message from Ian Lance Taylor:
Patch Set 6: -Commit-Queue
Please don’t reply on this GitHub thread. Visit golang.org/cl/607715. After addressing review feedback, remember to publish your drafts!
Message from Go LUCI:
Patch Set 6:
This CL has passed the run
Please don’t reply on this GitHub thread. Visit golang.org/cl/607715. After addressing review feedback, remember to publish your drafts!
Message from Go LUCI:
Patch Set 6: LUCI-TryBot-Result+1
Please don’t reply on this GitHub thread. Visit golang.org/cl/607715. After addressing review feedback, remember to publish your drafts!
This PR (HEAD: b7f979186022f1a7ff6e6445ed22319b12c74a67) has been imported to Gerrit for code review.
Please visit Gerrit at https://go-review.googlesource.com/c/go/+/607715.
Important tips:
- Don't comment on this PR. All discussion takes place in Gerrit.
- You need a Gmail or other Google account to log in to Gerrit.
- To change your code in response to feedback:
- Push a new commit to the branch used by your GitHub PR.
- A new "patch set" will then appear in Gerrit.
- Respond to each comment by marking as Done in Gerrit if implemented as suggested. You can alternatively write a reply.
- Critical: you must click the blue Reply button near the top to publish your Gerrit responses.
- Multiple commits in the PR will be squashed by GerritBot.
- The title and description of the GitHub PR are used to construct the final commit message.
- Edit these as needed via the GitHub web interface (not via Gerrit or git).
- You should word wrap the PR description at ~76 characters unless you need longer lines (e.g., for tables or URLs).
- See the Sending a change via GitHub and Reviews sections of the Contribution Guide as well as the FAQ for details.
Message from Aperence Ark:
Patch Set 6:
(2 comments)
Please don’t reply on this GitHub thread. Visit golang.org/cl/607715. After addressing review feedback, remember to publish your drafts!
Message from Ian Lance Taylor:
Patch Set 7:
(1 comment)
Please don’t reply on this GitHub thread. Visit golang.org/cl/607715. After addressing review feedback, remember to publish your drafts!