Since commit 500462a9de ("timers: Switch to a non-cascading wheel"),
timers duration can last even 12.5% more than the scheduled interval.
IPVS has two handlers, /proc/net/ip_vs_conn and /proc/net/ip_vs_conn_sync,
which shows the remaining time before that a connection expires.
The default expire time for a connection is 60 seconds, and the
expiration timer can fire even 4 seconds later than the scheduled time.
The expiration time is calculated subtracting jiffies to the scheduled
expiration time, and it's shown as a huge number when the timer fires late,
since both values are unsigned.
This can confuse script and tools which relies on it, like ipvsadm:
root@mcroce-redhat:~# while ipvsadm -lc |grep SYN_RECV; do sleep 1 ; done
TCP 00:05 SYN_RECV [fc00:1::1]:55732 [fc00:1::2]:8000 [fc00:2000::1]:8000
TCP 00:04 SYN_RECV [fc00:1::1]:55732 [fc00:1::2]:8000 [fc00:2000::1]:8000
TCP 00:03 SYN_RECV [fc00:1::1]:55732 [fc00:1::2]:8000 [fc00:2000::1]:8000
TCP 00:02 SYN_RECV [fc00:1::1]:55732 [fc00:1::2]:8000 [fc00:2000::1]:8000
TCP 00:01 SYN_RECV [fc00:1::1]:55732 [fc00:1::2]:8000 [fc00:2000::1]:8000
TCP 00:00 SYN_RECV [fc00:1::1]:55732 [fc00:1::2]:8000 [fc00:2000::1]:8000
TCP 68719476:44 SYN_RECV [fc00:1::1]:55732 [fc00:1::2]:8000 [fc00:2000::1]:8000
TCP 68719476:43 SYN_RECV [fc00:1::1]:55732 [fc00:1::2]:8000 [fc00:2000::1]:8000
TCP 68719476:42 SYN_RECV [fc00:1::1]:55732 [fc00:1::2]:8000 [fc00:2000::1]:8000
TCP 68719476:41 SYN_RECV [fc00:1::1]:55732 [fc00:1::2]:8000 [fc00:2000::1]:8000
TCP 68719476:40 SYN_RECV [fc00:1::1]:55732 [fc00:1::2]:8000 [fc00:2000::1]:8000
TCP 68719476:39 SYN_RECV [fc00:1::1]:55732 [fc00:1::2]:8000 [fc00:2000::1]:8000
Signed-off-by: Matteo Croce <mcroce@redhat.com>
Acked-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>