[c-nsp] Strange drops on 6500

[Tantsura, Jeff]

Hi,

I've got following problem:
There are 2 6500 Sup1a 12.1(8a)EX connected by 2 dark fibers on 2 different
blades.
There's about 20Mb/5000 pps on every link (bound as etherchannel)
Both links drop about 20-30 pps in outgoing direction.
Please find the configuration below.
Thanks in advance,
Jeff

interface GigabitEthernet1/1
  mtu 1508
 no ip address
 mls qos trust ip-precedence
 switchport
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 20,25,30,901,903,959-966,1002-1005
 switchport mode trunk
 channel-group 1 mode desirable

interface GigabitEthernet2/1
 mtu 1508
 no ip address
 mls qos trust ip-precedence
 switchport
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 20,25,30,901,903,959-966,1002-1005
 switchport mode trunk
 channel-group 1 mode desirable

interface Port-channel1
 mtu 1508
 no ip address
 mls qos trust ip-precedence
 switchport
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 20,25,30,901,903,959-966,1002-1005
 switchport mode trunk
 spanning-tree vlan 901 cost 65535
 spanning-tree vlan 903 cost 65535
 spanning-tree vlan 959 cost 65535
 spanning-tree vlan 962 cost 65535
 spanning-tree vlan 963 cost 65535
 spanning-tree vlan 966 cost 65535
 spanning-tree cost 3


GigabitEthernet1/1 is up, line protocol is up 
  Hardware is C6k 1000Mb 802.3, address is 0005.5f2c.be70 (bia
0005.5f2c.be70)
  MTU 1508 bytes, BW 1000000 Kbit, DLY 10 usec, 
     reliability 255/255, txload 5/255, rxload 5/255
  Encapsulation ARPA, loopback not set
  Full-duplex, 1000Mb/s
  ARP type: ARPA, ARP Timeout 04:00:00
  Last input 2y7w, output 2y7w, output hang never
  Last clearing of "show interface" counters 17:26:57
  Input queue: 0/2000/0/0 (size/max/drops/flushes); Total output drops:
475088
  Queueing strategy: fifo
  Output queue :0/40 (size/max)
  5 minute input rate 20063000 bits/sec, 5400 packets/sec
  5 minute output rate 22552000 bits/sec, 5229 packets/sec
     390754099 packets input, 203856992684 bytes, 0 no buffer
     Received 533410 broadcasts, 0 runts, 0 giants, 0 throttles
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
     0 input packets with dribble condition detected
     369139897 packets output, 184429171061 bytes, 0 underruns
     0 output errors, 0 collisions, 0 interface resets
     0 babbles, 0 late collision, 0 deferred
     0 lost carrier, 0 no carrier
     0 output buffer failures, 0 output buffers swapped out

Hardware is C6k 1000Mb 802.3, address is 0005.5f2c.bea8 (bia 0005.5f2c.bea8)
  Description: FR-CHP-SA-04 GE.2.2 CHAMPAGNE 1GBITS ZX
  MTU 1508 bytes, BW 1000000 Kbit, DLY 10 usec, 
     reliability 255/255, txload 1/255, rxload 1/255
  Encapsulation ARPA, loopback not set
  Full-duplex, 1000Mb/s
  ARP type: ARPA, ARP Timeout 04:00:00
  Last input 2y7w, output 2y7w, output hang never
  Last clearing of "show interface" counters 17:27:10
  Input queue: 0/2000/0/0 (size/max/drops/flushes); Total output drops:
475186
  Queueing strategy: fifo
  Output queue :0/40 (size/max)
  5 minute input rate 2729000 bits/sec, 527 packets/sec
  5 minute output rate 2398000 bits/sec, 490 packets/sec
     15908082 packets input, 6661511961 bytes, 0 no buffer
     Received 1601550 broadcasts, 0 runts, 0 giants, 0 throttles
     50 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
     0 input packets with dribble condition detected
     14086196 packets output, 4473718198 bytes, 0 underruns
     0 output errors, 0 collisions, 0 interface resets
     0 babbles, 0 late collision, 0 deferred
     0 lost carrier, 0 no carrier
     0 output buffer failures, 0 output buffers swapped out