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From: "Eugene M. Zheganin" <emz@norma.perm.ru>
Subject: sonewconn: pcb [...]: Listen queue overflow to human-readable form
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Date: Thu, 15 Dec 2016 17:23:44 +0500
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Hi.

Sometimes on one of my servers I got dmesg full of

sonewconn: pcb 0xfffff80373aec000: Listen queue overflow: 49 already in
queue awaiting acceptance (6 occurrences)
sonewconn: pcb 0xfffff80373aec000: Listen queue overflow: 49 already in
queue awaiting acceptance (2 occurrences)
sonewconn: pcb 0xfffff80373aec000: Listen queue overflow: 49 already in
queue awaiting acceptance (1 occurrences)
sonewconn: pcb 0xfffff80373aec000: Listen queue overflow: 49 already in
queue awaiting acceptance (15 occurrences)
sonewconn: pcb 0xfffff80373aec000: Listen queue overflow: 49 already in
queue awaiting acceptance (12 occurrences)
sonewconn: pcb 0xfffff80373aec000: Listen queue overflow: 49 already in
queue awaiting acceptance (10 occurrences)
sonewconn: pcb 0xfffff80373aec000: Listen queue overflow: 49 already in
queue awaiting acceptance (16 occurrences)
sonewconn: pcb 0xfffff80373aec000: Listen queue overflow: 49 already in
queue awaiting acceptance (16 occurrences)
sonewconn: pcb 0xfffff80373aec000: Listen queue overflow: 49 already in
queue awaiting acceptance (22 occurrences)
sonewconn: pcb 0xfffff80373aec000: Listen queue overflow: 49 already in
queue awaiting acceptance (6 occurrences)
sonewconn: pcb 0xfffff80373aec000: Listen queue overflow: 49 already in
queue awaiting acceptance (6 occurrences)
sonewconn: pcb 0xfffff80373aec000: Listen queue overflow: 49 already in
queue awaiting acceptance (1 occurrences)
sonewconn: pcb 0xfffff80373aec000: Listen queue overflow: 49 already in
queue awaiting acceptance (9 occurrences)
sonewconn: pcb 0xfffff80373aec000: Listen queue overflow: 49 already in
queue awaiting acceptance (5 occurrences)
sonewconn: pcb 0xfffff80373aec000: Listen queue overflow: 49 already in
queue awaiting acceptance (18 occurrences)
sonewconn: pcb 0xfffff80373aec000: Listen queue overflow: 49 already in
queue awaiting acceptance (4 occurrences)

but at the time of investigation the socket is already closed and lsof
cannot show me the owner. I wonder if the kernel can itself decode this
output and write it in the human-readable form ?

Thanks.
Eugene.