Thanks for the responses, Nick. I may have previously framed the problem in a biased way.
What I should have said is this: Since upgrading my Guacamole server from v1.1.0 to v1.5.5, both myself and other users have been experiencing random timeouts while connected to VNC. Before the upgrade, we had never encountered the 408 timeout message—the one that suggests a spotty network connection. However, since upgrading to v1.5.5, we have started experiencing this issue. I initially focused on resource management because I believed it was the primary cause of these timeouts. However, I’ve realized that wasn’t the best approach. I’m now curious if there are other changes across the releases that might be contributing to this behavior. Is there code worth looking at that could help explain this? Any bit of detail is much appreciated. Thanks! Get Outlook for iOS<https://aka.ms/o0ukef> ________________________________ From: Nick Couchman <vn...@apache.org> Sent: Sunday, March 2, 2025 2:13:27 PM To: user@guacamole.apache.org <user@guacamole.apache.org> Subject: Re: VNC sessions intermittently time out with HTTP error code 408 On Fri, Feb 28, 2025 at 3:31 PM Elijah <eli.ols...@gmail.com<mailto:eli.ols...@gmail.com>> wrote: Hello Guacamole Community, I’ve been experiencing intermittent user timeouts while using Apache Guacamole 1.5.5, and I’m trying to determine whether the issue is related to network conditions, or client-side system memory management. I wanted to reach out to see if anyone else has encountered similar behavior or has insights into potential causes. Issue Description: • Users are randomly timed out while actively using Guacamole. • This occurs more frequently when many Guacamole connections are open and when I have a lot of system processes running on my local machine. • I suspect this could be due to browser behavior, specifically the deallocation of memory from inactive tabs, or system/network resource limitations. I suspect you are correct about this - we've seen issues with recent versions of browsers that try to recover unused resources from tabs that are not active. Also, I see this happen periodically on my system when I'm close to limitations on system resources. Troubleshooting Considerations: 1. Browser Tab Inactivity: • Could browser memory management or resource deallocation be impacting Guacamole sessions? Yes. • Are there known browser-related session handling issues that might cause timeouts if a tab is deprioritized? I don't know about "known" - most of the issues are anecdotal and tend to come and go with various browser updates. 2. Server/System Performance: • When the number of open Guacamole sessions increases, could system resource exhaustion (e.g., CPU, RAM) contribute to unexpected disconnects? Yes. • Are there recommended settings for optimizing performance in environments with a high number of active sessions? IIRC, for guacd, the general guidance was 1 core and 4GB of RAM per 25 concurrent/active connections. Tomcat/Guacamole Client shouldn't need much in the way of resources - it simply facilitates the connection between the browser and guacd, and handles administrative stuff. 3. Network Conditions: • Is there any mechanism within Guacamole that aggressively times out sessions based on network instability? I would not say that there is any mechanism that _agressively_ times out sessions. Yes, Guacamole does check for network stability and will shut down a connection if it is lost, but I would say it is rather forgiving, not aggressive. • Would tweaking keep-alive settings or heartbeat intervals help mitigate this? I doubt it - I suspect the issues have more to do with the browser and/or client trying to manage the resources on the client, and I think this has more to do with whether the client tabs/windows are active or not. -Nick
