I have a Cisco ASA 5510 connecting our office via 2Mbit/s Internet. When Internet link fills up, latency to a well-connected host on Internet goes from 5-8 ms to 500-800 ms. With ping, it may look something like this (TCP performance seems to match this):
64 bytes from X: icmp_req=242 ttl=59 time=450 ms
64 bytes from X: icmp_req=243 ttl=59 time=458 ms
64 bytes from X: icmp_req=244 ttl=59 time=495 ms
64 bytes from X: icmp_req=245 ttl=59 time=186 ms
64 bytes from X: icmp_req=246 ttl=59 time=103 ms
64 bytes from X: icmp_req=247 ttl=59 time=5.18 ms
64 bytes from X: icmp_req=248 ttl=59 time=4.94 ms
64 bytes from X: icmp_req=249 ttl=59 time=4.65 ms
64 bytes from X: icmp_req=250 ttl=59 time=4.85 ms
I assume this is because large send queues on the 2 Mbit link. Since this is mainly office IT (from < 20 ppl), lateny is more important than throughput.
How can I measure how this latency is divided between outbound and inbound leg? If it turns out to be generated equally or mostly on inbound traffic, can I affect that (i.e. ingress throttling) or do I have to contact my ISP? How best to achieve this on ASA 8.2?
UPDATE: Short topolgy:
Ping node -[gbit]->
ProCurve dist -[gbit]->
ProCurve core -[gbit]->
ASA -[100 mbit]->
DSL -[copper]->
upstream
ASA interface upstream:
asa# show interface Ethernet 0/3
Interface Ethernet0/3 "outside", is up, line protocol is up
Hardware is i82546GB rev03, BW 100 Mbps, DLY 100 usec
Auto-Duplex(Full-duplex), Auto-Speed(100 Mbps)
Input flow control is unsupported, output flow control is off
Description: ### Upstream ###
MAC address X, MTU 1500
IP address X, subnet mask 255.255.255.252
3480433364 packets input, 2625479988848 bytes, 0 no buffer
Received 1010728 broadcasts, 0 runts, 11 giants
11 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
0 pause input, 0 resume input
0 L2 decode drops
3160567056 packets output, 1537515646562 bytes, 0 underruns
0 pause output, 0 resume output
0 output errors, 0 collisions, 15 interface resets
0 late collisions, 0 deferred
6 input reset drops, 0 output reset drops, 0 tx hangs
input queue (blocks free curr/low): hardware (255/240)
output queue (blocks free curr/low): hardware (255/109)
Traffic Statistics for "outside":
3487933998 packets input, 2561681053821 bytes
3160334264 packets output, 1477359288037 bytes
57746233 packets dropped
1 minute input rate 193 pkts/sec, 209755 bytes/sec
1 minute output rate 122 pkts/sec, 12734 bytes/sec
1 minute drop rate, 1 pkts/sec
5 minute input rate 177 pkts/sec, 174578 bytes/sec
5 minute output rate 131 pkts/sec, 17600 bytes/sec
5 minute drop rate, 2 pkts/sec