From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: "tm->when" at /proc/net/tcp shows some negative numbers.
Date: Mon, 11 Jul 2011 19:28:20 +0200
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To: Andreas O <andreas2025@gmail.com>
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Le lundi 11 juillet 2011 =C3=A0 17:47 +0100, Andreas O a =C3=A9crit :
> Dear devnet list,
>=20
> I am doing some performance improvements on  linux-2.6.33.15 with
> real-time support. When my tests fails I observe that "tm->when" at
> /proc/net/tcp shows
> some negative numbers. That negative number is the difference  of
> "timer_expires - jeffies" and in this case timer_expires is smaller
> than jiffies.
> Does this negative number indicates a bug in the stack?
>=20
>=20

Not necessarly.

If the thread handling timers is delayed (because of other more urgent
RT things), the delay between timer is fired and handled could be long.