Periodic traceback in log

[J. Max Mena]

I'm getting a periodic traceback in the server log while watching videos (YouTube? in Firefox/Chrome? or even just a local video file). As far as I can tell it doesn't appear to have a notable effect on anything, but that's just from my cursory exploration.

The server is a Fedora 26 2.X trunk r18005, and the client is at the same version as well.

My server is started with xpra start :13 --bind-tcp=0.0.0.0: --start-via-proxy=no --start-new-commands=yes --start-child=xterm --start-child="xterm -bg black -cr white -fg white" --start-child="xterm -bg black -fg white -cr white" and the client is attached without any special commands.

Here is the traceback:

Traceback (most recent call last):
  File "/usr/lib64/python2.7/site-packages/xpra/server/source.py", line 585, in recalculate_delays
    len(maximized_wids)>0 and wid not in maximized_wids)
  File "/usr/lib64/python2.7/site-packages/xpra/server/window/window_source.py", line 1052, in calculate_batch_delay
    calculate_batch_delay(self.wid, self.window_dimensions, has_focus, other_is_fullscreen, other_is_maximized, self.is_OR, self.soft_expired, self.batch_config, self.global_statistics, self.statistics, self.bandwidth_limit)
  File "/usr/lib64/python2.7/site-packages/xpra/server/window/batch_delay_calculator.py", line 39, in calculate_batch_delay
    factors = statistics.get_factors(bandwidth_limit)
  File "/usr/lib64/python2.7/site-packages/xpra/server/window/window_stats.py", line 142, in get_factors
    used = sum(v[4] for v in self.encoding_stats if v[0]>cutoff) * 8
  File "/usr/lib64/python2.7/site-packages/xpra/server/window/window_stats.py", line 142, in <genexpr>
    used = sum(v[4] for v in self.encoding_stats if v[0]>cutoff) * 8
RuntimeError: deque mutated during iteration

I've only noticed this since I've been watching more videos than normal while trying to figure out sound sync. I'm honestly not sure of the impact, as such I'll mark this ticket as minor.

[Antoine Martin]

Fixed in r18006, backport in r18007.

[migration script]

this ticket has been moved to: ​https://github.com/Xpra-org/xpra/issues/1743