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Changes between Initial Version and Version 2 of Ticket #21

10/15/11 18:14:02 (10 years ago)
Antoine Martin


  • Ticket #21

    • Property Status changed from new to accepted
    • Property Summary changed from high latency link causes keys to repeat to jitter on link causes keys to repeat
  • Ticket #21 – Description

    initial v2  
    11Solutions proposed:
    22* doing the key repeat client-side - this does not seem to be a workable solution, it is likely to break applications which are currently working just fine
     3* a better approach would be to require the client to confirm the key repeat within a certain amount of time: that way we can keep the key pressed on the server side, but we unpress it if we don't receive a "key-still-pressed" from the client in time. This allows us to maintain a consistent server-side state but we can also detect jitter on the line and take appropriate counter measures. (if we do eventually get the "key-still-pressed" packet after the timeout, we just press it again). The downside is that the line jitter will probably still cause keys to be pressed more than once (probably twice), just not dozens of times as it is now. Difficulty comes from the fact that the key-repeat delay is configurable and that it may well be shorter than the connection's transmit time when accounting for jitter.. And that we would need to communicate this delay to the client, and that those "key-still-pressed" messages waste precious bandwidth (although hardly more so than the pure client-side option)
    34* letting the server increase the key repeat delay - we probably would need some kind of timing information with the packets so the server can have an idea of latency (this may be worth having in any case)
    45* sending key events ahead of anything else (even mouse motion?) - this would not solve all cases, but work for cases where the high latency is caused by xpra packets