Fix out_forward keepalive reuse after remote close#5309
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aviralgarg05 wants to merge 1 commit intofluent:masterfrom
Open
Fix out_forward keepalive reuse after remote close#5309aviralgarg05 wants to merge 1 commit intofluent:masterfrom
aviralgarg05 wants to merge 1 commit intofluent:masterfrom
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Signed-off-by: aviralgarg05 <gargaviral99@gmail.com>
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Which issue(s) this PR fixes:
Fixes #5269
What this PR does / why we need it:
This PR fixes a keepalive socket reuse bug in
out_forward.When a cached keepalive connection has already been closed by the remote side,
out_forwardcould pick that socket back up and try to write to it again. In the reported TLS/NLB setup, that leaves the flush thread spinning on a dead socket and can drive CPU usage to 100%.The fix is to validate cached sockets before reusing them. If a socket has already become unreadable, closed, or otherwise looks no longer safe to reuse, it is discarded and a new connection is created instead.
This keeps
out_forwardfrom reusing half-closed keepalive sockets and avoids the busy-loop behavior described in the issue.This PR also adds regression coverage to make sure a socket that was closed by the peer is not reused from the keepalive cache.
Docs Changes:
None.
Release Note: