Listing the routing table takes long time to complete

Posted by Rafal Rawicki on Server Fault See other posts from Server Fault or by Rafal Rawicki
Published on 2012-06-10T19:25:02Z Indexed on 2012/06/11 16:42 UTC
Read the original article Hit count: 275

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linux

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linux-networking

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route

When I print routes defined on my computer using route, it takes about 5 to 20 seconds to complete. Why does it take so much time?

With VPN enabled:

$ time sudo route
Kernel IP routing table
(...)
real    0m21.423s
user    0m0.000s
sys 0m0.012s

With no VPN, this is about 5 seconds - still, computer can do a lot in this time. I've repeated my measurements few times, getting very similar results each try.

My machine is Ubuntu with 3.0.0 kernel, but as far as I know, route on the other computers works the same way.

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