2.6.36.2 - loop on read /proc/net/tcp
From: Alexey Vlasov
Date: Wed Dec 22 2010 - 09:07:44 EST
Hi.
Has anyone seen such a bug at 2.6.36.2?
# netstat -ntl
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address Foreign Address State
tcp 0 0 81.176.228.2:60608 0.0.0.0:* LISTEN
tcp 0 0 81.176.228.4:8099 0.0.0.0:* LISTEN
tcp 0 0 81.176.228.5:8099 0.0.0.0:* LISTEN
tcp 0 0 81.176.228.7:8099 0.0.0.0:* LISTEN
tcp 0 0 81.176.228.4:8100 0.0.0.0:* LISTEN
tcp 0 0 81.176.228.5:8100 0.0.0.0:* LISTEN
tcp 0 0 81.176.228.4:8101 0.0.0.0:* LISTEN
tcp 0 0 81.176.228.5:8101 0.0.0.0:* LISTEN
tcp 0 0 81.176.228.5:20037 0.0.0.0:* LISTEN
tcp 0 0 81.176.228.4:8102 0.0.0.0:* LISTEN
tcp 0 0 81.176.228.5:8102 0.0.0.0:* LISTEN
tcp 0 0 127.0.0.1:3399 0.0.0.0:* LISTEN
tcp 0 0 81.176.228.4:20040 0.0.0.0:* LISTEN
tcp 0 0 81.176.228.4:38985 0.0.0.0:* LISTEN
tcp 0 0 0.0.0.0:873 0.0.0.0:* LISTEN
tcp 0 0 81.176.228.4:20041 0.0.0.0:* LISTEN
tcp 0 0 81.176.228.4:20042 0.0.0.0:* LISTEN
tcp 0 0 81.176.228.4:3306 0.0.0.0:* LISTEN
tcp 0 0 81.176.228.3:3306 0.0.0.0:* LISTEN
tcp 0 0 81.176.228.2:3306 0.0.0.0:* LISTEN
tcp 0 0 81.176.228.5:9099 0.0.0.0:* LISTEN
tcp 0 0 81.176.228.4:9099 0.0.0.0:* LISTEN
tcp 0 0 81.176.228.4:20043 0.0.0.0:* LISTEN
tcp 0 0 0.0.0.0:139 0.0.0.0:* LISTEN
tcp 0 0 81.176.228.5:9100 0.0.0.0:* LISTEN
tcp 0 0 81.176.228.4:9100 0.0.0.0:* LISTEN
tcp 0 0 81.176.228.4:20044 0.0.0.0:* LISTEN
tcp 0 0 81.176.228.5:33549 0.0.0.0:* LISTEN
...
First 30 lines are ok
but then go lines repeating in "eternal" loop:
tcp 0 0 81.176.228.2:80 0.0.0.0:* LISTEN
tcp 0 0 81.176.228.3:80 0.0.0.0:* LISTEN
tcp 0 0 81.176.228.4:80 0.0.0.0:* LISTEN
tcp 0 0 81.176.228.7:80 0.0.0.0:* LISTEN
tcp 0 0 81.176.228.2:80 0.0.0.0:* LISTEN
tcp 0 0 81.176.228.3:80 0.0.0.0:* LISTEN
tcp 0 0 81.176.228.4:80 0.0.0.0:* LISTEN
tcp 0 0 81.176.228.7:80 0.0.0.0:* LISTEN
tcp 0 0 81.176.228.2:80 0.0.0.0:* LISTEN
tcp 0 0 81.176.228.3:80 0.0.0.0:* LISTEN
tcp 0 0 81.176.228.4:80 0.0.0.0:* LISTEN
tcp 0 0 81.176.228.7:80 0.0.0.0:* LISTEN
tcp 0 0 81.176.228.2:80 0.0.0.0:* LISTEN
# cat /proc/net/tcp
...
It can hang an hour or so. but not always actually.
# i=0; while [ "$i" -lt "10" ]; do time wc -l /proc/net/tcp; let "i = $i + 1"; done
614782727 /proc/net/tcp
real 18m42.066s
user 0m12.620s
sys 18m25.890s
19443 /proc/net/tcp
real 0m0.040s
user 0m0.000s
sys 0m0.030s
19503 /proc/net/tcp
real 0m0.040s
sys 0m0.030s
19502 /proc/net/tcp
real 0m0.041s
user 0m0.000s
sys 0m0.040s
28525 /proc/net/tcp
real 0m0.059s
user 0m0.000s
sys 0m0.050s
19463 /proc/net/tcp
real 0m0.048s
user 0m0.000s
sys 0m0.040s
19521 /proc/net/tcp
real 0m0.040s
user 0m0.000s
sys 0m0.030s
54394 /proc/net/tcp
real 0m0.104s
user 0m0.000s
sys 0m0.100s
19479 /proc/net/tcp
real 0m0.040s
user 0m0.000s
sys 0m0.030s
19481 /proc/net/tcp
real 0m0.040s
user 0m0.000s
sys 0m0.030s
--
BRGDS. Alexey Vlasov.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/