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Changes between Version 8 and Version 9 of SessionInfo


Ignore:
Timestamp:
08/28/14 10:00:23 (6 years ago)
Author:
Antoine Martin
Comment:

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  • SessionInfo

    v8 v9  
    4545= Statistics =
    4646
    47 The statistics pane shows various latency and quality data from the server, it can be used to monitor how well the system is self tuning to adapt to the network conditions:
    48 * {{{Server Latency (ms)}}}: this is a measure of how long it takes for:
    49  * the client to send a "ping" packet
    50  * the server to receive it, process it and send the "echo" response
    51  * the client to process the response and calculate the latency
    52 
    53   It is very different from an [http://en.wikipedia.org/wiki/Ping_(networking_utility) ICMP Ping] because it includes on both ends: the full operating system network stack, the operating system scheduler, the Python interpreter with its threads and locking, TCP re-transmits. On a busy system, this value may well go up as other packets are ahead of the send queue at either end. A modern CPU should be able to keep this value around 50ms plus the TCP connection latency (TCP packet drops can cause this value to increase more dramatically).
     47The statistics pane shows various latency and quality data from the server, it can be used to monitor how well the system is self tuning to adapt to the network conditions.
    5448
    5549You can see a screenshot [/attachment/wiki/SessionInfo/session-info-statistics.png here]
     50
     51
     52== Server Latency (ms) ==
     53This is a measure of how long it takes for:
     54* the client to send a "ping" packet
     55* the server to receive it, process it and send the "echo" response
     56* the client to process the response and calculate the latency
     57
     58It is very different from an [http://en.wikipedia.org/wiki/Ping_(networking_utility) ICMP Ping] because it includes ''on both ends'':
     59* the full operating system network stack
     60* the operating system scheduler
     61* the Python interpreter with its threads and locking
     62* TCP re-transmits
     63
     64On a busy system, this value may well go up as other packets are ahead of the send queue at either end.
     65A modern CPU should be able to keep this value below 50ms plus the TCP connection latency. TCP packet drops can cause this value to increase more dramatically.
     66
    5667}}}