xpra icon
Bug tracker and wiki

Changes between Initial Version and Version 3 of Ticket #1911


Ignore:
Timestamp:
07/08/18 11:15:55 (19 months ago)
Author:
Antoine Martin
Comment:

The batch delay increased rapidly because of congestion events and bandwidth limits:

2018-07-07 21:38:09,208 update_batch_delay: bandwidth-limit              : 6.77,45.88  {'used': 32245920, 'budget': 5242880}
2018-07-07 21:38:09,209 update_batch_delay: congestion                   : 1.87,8.74  {}

And sometimes also because of client-latency:

2018-07-07 21:38:23,080 update_batch_delay: client-latency               : 2.86,0.69  {'target': 8, 'weight_multiplier': 503, 'smoothing': 'sqrt', 'aim': 800, 'aimed_avg': 8178, 'div': 1000, 'avg': 233, 'recent': 446}

And to a lesser extent the client decode speed:

2018-07-07 21:38:27,286 update_batch_delay: client-decode-speed          : 2.15,4.59  {'avg': 131, 'recent': 449}

This all points towards a network / CPU performance bottleneck on the client.


You can now turn off bandwidth detection more easily, see #1912.

With this turned off, it should now be impossible to get update_batch_delay: congestion to raise the batch delay since the congestion-value should always be zero. (it is calculated from the congestion_send_speed list which is only updated in record_congestion_event and this method is bypassed when bandwidth detection is turned off).

This won't fix the massive jitter you are seeing though:

  • this is very wrong (1.2 second for getting the paint packet ack):
    2018-07-08 10:59:12,969 record_latency: took 1294.6 ms round trip, 1294.5 for echo,   14.0 for decoding of      240 pixels,       59 bytes sent over the network in 1280.4 ms, 1280.3 ms for echo
    
  • whereas later it goes fine for similar (tiny) packets later:
    2018-07-08 10:59:30,733 record_latency: took   14.3 ms round trip,   14.3 for echo,    1.0 for decoding of    44888 pixels,       60 bytes sent over the network in   12.8 ms,   12.7 ms for echo
    

Legend:

Unmodified
Added
Removed
Modified
  • Ticket #1911

    • Property Owner changed from Antoine Martin to tc424
    • Property Milestone changed from to 2.4
  • Ticket #1911 – Description

    initial v3  
    11Opening ticket after [https://pastebin.com/WbDvhrs8 this discussion] on IRC.
    22
    3 Using 2.3.2 on Ubuntu 14.04 and 18.04 over wifi, 1Gb/s ethernet and local I see performance which starts out as fairly poor and then spirals rapidly out of control.
     3Using 2.3.2 on Ubuntu 16.04 and 18.04 over wifi, 1Gb/s ethernet and local I see performance which starts out as fairly poor and then spirals rapidly out of control.
    44
    55Have attached bug report tool output from the 18.04 machine used in local mode (mmap enabled.)