Retry UDP request on timeout before giving up#7
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mcfnord wants to merge 1 commit intosoftins:masterfrom
Open
Retry UDP request on timeout before giving up#7mcfnord wants to merge 1 commit intosoftins:masterfrom
mcfnord wants to merge 1 commit intosoftins:masterfrom
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Replace the single 1.5s socket timeout with a 500ms timeout and up to 3 attempts. If no data is received within the window, the same request is re-sent. This recovers from dropped UDP packets without increasing the worst-case wait time beyond the original 1.5s.
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I haven't run this in production. Will do so and report results here. |
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Summary
SO_RCVTIMEOwith a 500ms timeout and up to 3 attemptsrecvfromwaits againMotivation
UDP is inherently lossy. The original code made one attempt and either succeeded or silently returned nothing to the client. Under any packet loss — even transient — the directory or server query would fail completely. The retry loop makes the behaviour consistent with what users expect from a web page fetching live server lists.
Test plan
anygenre1.jamulus.io:22124is ~142ms, well within the 500ms windowiptables40% random UDP drop rule and ran 20 requests: attempt-2 recoveries worked correctly, attempt-3 recoveries worked correctly, total-failure rate matched expectedp³probability