GUACAMOLE-1846: Synchronize new users to connections in batches to fix join race condition. #455
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Oh cool, this issue/fix sounds like it might be related to what I was seeing in #316 (comment) |
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Marking as draft while I investigate an issue. |
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Ok, I think this should be ready to go again. I'm still seeing the client occasionally get locked up when shutting down and fail to shut down cleanly, but at least it's guaranteed to always shut down with the new shutdown handling introduced in eaca340. |
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This was an issue with lock acquisition/release order and has been fixed.
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@jmuehlner, as a bug fix should this be against |
Uh, yeah, I suppose so. Let me retarget it. It's done |
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…g user promotion.
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This change turned out to be pretty involved, but at their core, these changes are addressing the race condition described in GUACAMOLE-1846.
This change addresses this problem by batching up all newly connected users and synchronizing connection state to them using a newly defined
join_pending_handler, at which time they'll be promoted to full users, and the broadcast socket will write to them.This synchronization is done using a new broadcast socket that writes to all synchronized users at once, instead of once at a time.
Pending users are synchronized once every quarter second, which should result in little noticeable delay upon joining a connection.
Thanks to @mike-jumper for helping to work through the logic here and help figure out various bugs along the way.