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1.3.6 frequent 'Server closed connection" (reproducible)

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andrewk89
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1.3.6 frequent 'Server closed connection" (reproducible)

Post by andrewk89 »

1.3.6 on Windows 10 21H2 x64. A certain software / action is causing "Server closed connection" "-Manual closed" "-Network disconn". You can re-connect and continue. It seems to be reproducible.

Server is running in service mode. Poll Full Screen, System HookDLL and Low Accuracy (100% CPU) are checked. Legacy Capture auto.

Client is the same version, using Auto select both settings.

Both computers are on the same LAN. Both Wi-Fi. Both with 700-866 Mbps link speed (i.e. good signal strength).

The software is Shotcut. Windows x64 version 21.12.24. Using the "portable" (zip) version. Shotcut's GUI is built with Qt 5.15.2.
https://github.com/mltframework/shotcut ... /v21.12.24
  • Settings --> Video Mode --> Pick one
  • Drag / drop video into the GUI
  • Drag drop video from the preview window to the timeline
  • In the export presets, choose lossless --> H.264
  • Set Video Interpolation to Lanczos (best)
  • click Export File. Choose a file name
  • While that job is running in the background, click Export again
With high CPU usage (e.g. from a running encode), bringing up the Export File dialog will trigger a force close.

If you re-connect. Click Cancel on the export. Then click Export again. It will disconnect. Every time.

The key is to have an encode running in the background. Not sure if it is specific to the melt.exe process or simply running something that's using all cores. melt.exe is set to run at "Below Normal" priority, so the Windows process scheduler will readily give other processes (e.g. the VNC server) CPU cycles.

Edit: Windows Explorer can also trigger a disconnect most of the time. Left click a file. Right mouse button. Server will disconnect.

Edit: My computer is plenty fast to run a VNC server. Ryzen 7 3700X (8C/16T @ 3.6 GHz), 32 GB RAM, NVMe storage. Typical memory usage is 8-12 GB.
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Rudi De Vos
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Re: 1.3.6 frequent 'Server closed connection" (reproducible)

Post by Rudi De Vos »

Tried to repeat it.

With ddengine and without.
intel i7 16GB

shortcut comrpession to file
VNC server running
vncviewer running sharing a netflix screen on the second monitor.
CPU 100%
No disconnect

Without ddengine only a few frames a seconds, slow as hell, with ddengine 6 FPS.

Will try it again later on amd .
andrewk89
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Joined: 2016-04-06 22:38

Re: 1.3.6 frequent 'Server closed connection" (reproducible)

Post by andrewk89 »

After installing the W10 21H2 January update, I haven't had disconnects. Super annoying in Dec / Jan. Who knows whether there was something in the update or it just needed a reboot cycle to clean up something.
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