Listen queue overflow: N already in queue awaiting acceptance

Andriy Gapon avg at
Thu Jul 11 15:05:49 UTC 2013

on 11/07/2013 17:28 Andre Oppermann said the following:
> Andriy for example would never have found out about this problem other
> than receiving vague user complaints about aborted connection attempts.
> Maybe after spending many hours searching for the cause he may have
> interfered from endless scrolling in Wireshark that something wasn't
> right and blame syncache first.  Only later it would emerge that he's
> either receiving too many connections or his application is too slow
> dealing with incoming connections.

That's true, but OTOH there are many interesting network conditions like
excessive packet loss that we don't shout about.  The stats are quietly gathered
and can be examined with netstat.  If a system is properly monitored then such
counters are graphed and can trigger alarms.  If the system just misbehaves then
an administrator can use netstat for inspection.
Spamming logs in the case of e.g. DDoS attack is not very helpful, IMO.

Andriy Gapon

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