Mail Bridge Performance


Phill Gross (gross@mitre.ARPA)
Mon, 3 Mar 86 08:26:47 est


BAD MSG:
is, however, since the dropped packets account for only about 3% of
he total sent. So, although the mail bridges seem to drop more than
their share, it doesn't seem that dropped packets account for their
lousy performance. I've included output below analyzing a couple
of recent weeks. It's interesting that the mail bridges tend to have
longer packets than the rest of the gateways. Could that mean that
people really use the mail bridges for mail and us Telnet users are
in the minority? Anyone got any suggestions?

The percentages at the bottom are straight from the throughput reports
and, when boiled down, lead me to believe that no more than half
of the total traffic is real user data. The rest is system overhead
(gateway protocols and icmp). But that's different argument.

Mail Bridge Data from Gateway Throughtput Report for week of Jan 20
                      (38 total gateways)

                            datagrams bytes
Mail Bridge Rcvd Totals : 28529446 2824653776 (avg pkt len= 99.0 bytes)
LSI Gateway Rcvd Totals : 93635883 7532803988 (avg pkt len= 80.4 bytes)
MB percent of Rcvd Total: 30.468 37.498

Mail Bridge Sent Totals : 28529773 2808049620 (avg pkt len= 98.4 bytes)
LSI Gateway Sent Totals : 94735845 7345672471 (avg pkt len= 77.5 bytes)
MB percent of Sent Total: 30.115 38.227

Mail Bridge Dropped: 726513 (2.55% of MB total sent)
LSI Gateway Dropped: 1858797 (1.96% of LSI total sent)
MB percent of Drpd : 39.085

percent pkts addressed to gateways = 35.28
percent pkts originating at gateways= 38.43
percent pkts forwarded to gateways = 41.94

Mail Bridge Data from Gateway Throughtput Report for week of Jan 27
                      (39 total gateways)

                            datagrams bytes
Mail Bridge Rcvd Totals : 33340101 3096532134 (avg pkt len= 92.9 bytes)
LSI Gateway Rcvd Totals : 100841370 8846421595 (avg pkt len= 87.7 bytes)
MB percent of Rcvd Total: 33.062 35.003

Mail Bridge Sent Totals : 33046453 3209057088 (avg pkt len= 97.1 bytes)
LSI Gateway Sent Totals : 103236490 8169295835 (avg pkt len= 79.1 bytes)
MB percent of Sent Total: 32.010 39.282

Mail Bridge Dropped: 1333934 (4.04% of MB total sent)
LSI Gateway Dropped: 3098725 (3.00% of LSI total sent)
MB percent of Drpd : 43.048

percent pkts addressed to gateways = 42.79
percent pkts originating at gateways= 47.10
percent pkts forwarded to gateways = 48.41

I also decided to plot the traffic sent by the gateways and convinced
myself that I saw some interesting trends. In addition to a general
sensitivity in the data to holidays and school schedules, there has been
a definite upswing in traffic over the last 5-6 weeks. I've included the
plots below. It's great fun to try to figure out what it means.

Last year seems to start off with a plateau around 75 million packets
per week for the whole gateway system. After climbing and leveling to



This archive was generated by hypermail 2.0b3 on Thu Mar 09 2000 - 14:36:04 GMT