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Senior Member
Posts: 1
Registered: ‎02-26-2015

What does HWM mean in regards to performance information

Hello I'm doing some troubleshooting in regards to BNA 12.3 misreporting the round trip time on a FCIP tunnel as 100+ms where when we run fciptunnel -cp we get 1-2ms RTT. 

FOS 7.3.1b

portshow fciptunnel -cp     :

 

Tunnel Circuit   TxMBps RxMBps ComRatio RTT(ms)   ReTx OutOfSeq SlowStart

--------------------------------------------------------------------------------

4/20   -           2.60 212.80 1.82:1     -       6437   738353       91

4/20   0 4/xge1     2.60 212.80   -       1       6433   738325       87

4/20   1 4/xge0     0.00   0.00   -       2         4       28         4

--------------------------------------------------------------------------------

 

I was looking at the portshow fciptunnel -pctq --lifetime output and noticed this HWM value being reported but could not find a explaination of what HWM means.  I am guessing it is High Water Mark and that is the highest value seen over the lifetime of the link.  Does anyone have an documentation or insight into this acroymn and its meaning? 

 

 

 

 TCP Connection 4/20.0:2046863680
         Priority: F-Class
         Flags: 0x00000000
         Duration: 27d17h
         Local Port: 50527
         Remote Port: 3225
         Max Seg Size: 1360
         Adaptive Rate Limiting Statistics:
            None (F-Class)
         Sender Statistics:
            Bytes Sent: 229295328
            Packets Sent: 2092052
            Round Trip Time 1 ms, HWM 99 ms, Variance 0, HWM 91
            Send Window: 12499968 bytes, scale: 9
            Slow Starts: 5
            Slow Start Threshold: 16777216
            Congestion Window: 16778576
            TCP Op State: slow start
            Next Seq: 0x95ffaa23, Min: 0x95ffaa23, Max: 0x95ffaa23
            Unacked data: 0
            Retransmit Timeout: 100 ms, Duplicate ACKs 0
            Retransmits: 4, max: 1
            Fast ReTx: 0, HWM 0, Slow ReTx: 4
         Receiver Statistics:
            Bytes Received: 116667148
            Packets Received: 2091206
            Receive Window: 12499968 Bytes, max: 12499968
            Negotiated Window Scale: 9
            RecvQ Bytes: 0
            RecvQ Next: 0x0852d6cb Min: 0x0852d6cb Max: 0x091192cb
            Out Of Sequence Pkts: 4, HWM 4, Total 4
         Keepalive:
            Keepalive Timeout: 60 s
            Keepalive Interval: 15 s
            Inactivity: 120 s

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