In a support thread titled “Who’s online crazy load,” AGeneral reports that the “Who’s Online” plugin causes performance issues on their Discourse forum, despite running on a Lightsail instance with 8 GB RAM, 2 vCPUs, and 160 GB SSD. Disabling the plugin resolves the issue. merefield suggests the server may be underpowered for concurrent client connections, as the plugin relies on the Presence system for near real-time updates, recommending at least 3–4 CPU cores for such load. While memory and disk space are sufficient, CPU may be the bottleneck. In response, AGeneral asks if client messaging can be reduced, accepting slightly stale user status. merefield advises limiting plugin visibility via settings like whos_online_display_public and whos_online_display_min_trust_level to reduce load by restricting which users receive updates. No plugin-specific throttling settings are mentioned, but access control is offered as a mitigation strategy.
Hello, I posted my issues here, but I will recopy: Discourse Who's Online
This plugin (at least on our forum) gives the following message. When we turn off the plugin it goes away. Does anyone else have this issue? We have a more than sufficient server to handle the number of active users. Using Lightsail 8 GB RAM, 2 vCPUs, 160 GB SSD Ubuntu
This strikes me as under-powered from a concurrency perspective.
This plugin uses the Presence system which performs a reasonable amount of client messaging on an ongoing basis to maintain a semi-real-time view of who is online.
With that many clients connecting at once you might consider upping the number of CPUs to at least 3 if not 4 cores. I’m not sure I see the point of 8GB with only 2 cores? I believe one rough rule of thumb is 1 core per 2GB. Even my 4GB machines have 3 cores and I’m not even running this demanding plugin.
Memory and apparently disk space look generous, so no issues there!
Thank you! Is there any setting that we can reduce the amount of client messaging. We’re ok with the user status being a few minutes stale.
I’m not the author of the plugin but you might try limiting those who can see it, via settings:
whos_online_display_publicwhos_online_display_min_trust_levelto significantly limit who gets told.