From mboxrd@z Thu Jan  1 00:00:00 1970
From: cold cold <nedkonedev@gmail.com>
Subject: 0% cpu usasge after fresh boot or net restart but 10% CPU if kernel
	flush route cache
Date: Tue, 26 Jan 2010 18:58:31 +0200
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HI,


i have expiriance some CPU usage spikes=A0up to 10% on=A0each four cpus
after the=A0first kernel route cache flush.
After mashine start first 20 min CPU is 0%si=A0=A0300Mbits/s full duple=
x
and arount 100k pps forwarded traffic, without any firewall, just
plain routing.

route -n |wc -l
34

ip route show cache | wc -l
2140842

cat /proc/sys/net/ipv4/route/secret_interval
600
cat /proc/sys/net/ipv4/route/max_size
33554432

after kernel=A0 flush i got 10% on all CPUs for 5-6 mins.=A0 It's not f=
rom
rebuilding route cashe becouse=A0after
fresh boot or network restrat there is no=A0CPU usage until kernel flus=
h
route cache.
I try to play with rhash_entries=3D 300000=A0to 2000000 same result.

Network Card: Ethernet controller: Intel Corporation 82576 Gigabit
Network Connection
CPU: Intel(R) Xeon(R) CPU=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0 E5420=A0 @ 2.50=
GHz
RAM: 4G
Kernel: vanilla=A02.6.32.4