Use tcp_nodelay on socket server#537
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The sockets we use in this library should be optimized for real-time communication, not for throughput. Therefore, they should use tcp_nodelay by default.
urfeex
marked this pull request as draft
July 10, 2026 07:14
Codecov Report❌ Patch coverage is
Additional details and impacted files@@ Coverage Diff @@
## master #537 +/- ##
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- Coverage 79.16% 78.71% -0.46%
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Files 115 115
Lines 6769 6775 +6
Branches 2991 3000 +9
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- Hits 5359 5333 -26
- Misses 1040 1069 +29
- Partials 370 373 +3
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urfeex
marked this pull request as ready for review
July 10, 2026 07:23
michal-milkowski
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Jul 10, 2026
michal-milkowski
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Is nodelay also set on client socket?
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| ur_setsockopt(client_fd, IPPROTO_TCP, TCP_NODELAY, &flag, sizeof(int)); |
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- check return value. Warn if option can't be set.
- it's better to use sizeof(flag) instead.
- this could be attempted on closed socket on line 260. either check if accepted == true or move flag set somewhere up
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Thank you for the comments. I implemented those in c73d273
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| int flag = 1; |
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can be constexpr
Suggested change
| int flag = 1; | |
| constexpr int flag = 1; |
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Yes, it is: I've updated that to use the |
michal-milkowski
approved these changes
Jul 10, 2026
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The sockets we use in this library should be optimized for real-time communication, not for throughput. Therefore, they should use tcp_nodelay by default.
Note
Low Risk
Low-latency TCP tuning and non-fatal logging around setsockopt; no auth or data-model changes.
Overview
TCP sockets are tuned for lower latency by enabling
TCP_NODELAYon each accepted server connection (client outbound paths already set it inTCPSocket::setupOptions).Socket option setup is centralized in
setSocketOptionAndWarnOnError, which logs a warning whensetsockoptfails instead of ignoring errors. Listen socket options (SO_REUSEADDR,SO_KEEPALIVE) and client options (TCP_NODELAY,TCP_QUICKACK,SO_RCVTIMEO) now go through that helper.Reviewed by Cursor Bugbot for commit 21bab87. Bugbot is set up for automated code reviews on this repo. Configure here.