BGP routes are taking too long to Populate from upstream

[avora00011]

We have  a Cisco 6509 s72033_rp-ADVENTERPRISEK9-M), Version 15.1(2)SY4a and we receive full internet routing table from tier 2 provider, Problem is that whenever the peer goes down and when it comes back up it takes  forever to populate full internet routing table; almost about 8-9 hours to reach 500K+, of course we have other exit point or another tier 1 provider too but this thing is bugging me, do you guys have any thoughts on this ?

Thank you for your time,

[Joseph W. Doherty]

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Posting

On your router, is PMTUD enabled and TCP RWIN larger than the default?  Since BGP uses TCP, the optimal combination can often improve BGP's TCP bulk transfer rate.

You might also need to adjust the BGP interface's ingress queue, in case the BGP packets burst in faster than the control plane can manage.

[avora00011]

Hey thank you for the reply, PMTUD is not enabled; I dont know how to check TCP window size but if you could throw some examples on it that'd be great, and yes Queuing is there but its not touching TCP at all. let me know if you need any more info.

Thanks again, 

[Joseph W. Doherty]

Untitled Document

ip tcp window-size 65535
ip tcp path-mtu-discovery age-timer 10