[quagga-users 15019] %100 CPU usage in Quagga when MRAI timer is being set to zero
shahrooz at cs.umass.edu
Fri May 17 05:57:00 BST 2019
I am trying to do an experiment using Quagga. In my experiment, I need
to set the MRAI timer value to zero and measure the convergence time of
I am setting the MRAI timer value in Quagga which is
BGP_DEFAULT_EBGP_ROUTEADV to zero and run my BGP daemons.
Unfortunately, when I set the MRAI value to zero and establish a BGP
session between my two BGP daemons, I have %100 CPU usage!. The default
MRAI timer value for eBGP routers is 3 seconds which when I use the
default value of MRAI timer value, I do not have this %100 CPU usage
I am only changing the MRAI timer default value from 3 seconds to zero
and then I get % 100 CPU usage even if I just send one prefix from the
first BGP daemon to another one.
I found that if there is no relationship between each the BGP daemons,
we do not have this problem(%100 CPU usage). But even if we have just
two BGP daemons and they have customer-provider relationship, then we
have high CPU usage.
I searched and it seems there has been a problem like this but for zebra
daemon and for OSPF and iBGP routers( you can see the link of the
question here: https://github.com/FRRouting/frr/issues/1864). I am not
sure if this is related to my problem as I see this behavior with and
without zebra daemon running.
Does anyone have any explanation for this behavior in Quagga? I will be
really appreciated if someone can help me to explain this behavior.
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