Information Technology Reference
In-Depth Information
Figure 3-9 shows the results of the testing.
Figure 3-9
Peer Group and Path MTU Convergence Statistics
Peer Groups and Path MTU Discovery Convergence
200
500
180
450
160
400
140
350
120
300
100
250
80
200
60
150
40
100
20
50
0
0
70, 000
80, 000
90, 000
100, 000
110,000
120,000
130,000
140,000
Convergence Times
102
112
127
125
157
165
165
185
Input Drop Count
122
93
116
134
139
190
213
431
Prefix Count
The deployment of PMTUD should reduce the number of BGP updates by approximately
63%, which significantly reduces the number of input queue drops. The reduction in input
queue drops improves the TCP throughput on the BGP sessions. The increase in packet size
provides on average a 20% decrease in convergence time over peer groups.
Peer Groups and Queue Optimization
The input hold queues have been optimized to prevent input drops in addition to peer groups.
This optimization allows the TCP transport for the BGP peering sessions to operate without
retransmissions.
The BGP feature status is as follows:
•
Peer groups are enabled.
•
Path MTU Discovery is disabled (TCP MSS 536).
•
The input hold queue is 1000.
•
Update packing is not supported.
Figure 3-10 shows the results of the testing.
