I have seen substantial increase in CPU usage since upgrading this weekend. The CPU usage of RUBY appears to be the primary driver. This was referenced by another discourse user in this topic . As you can see from the graphs below, CPU usage and load pre-upgrade were much lower than post-upgrade. Th…

Lets leave this in support for a bit till we determine if there is a bug. Can you enter the container and run an htop from the inside (you will have to install it) that way you will be able to tell which specific process is consuming high amounts of cpu. You can get a bit more visibility using a t…

htop views. Here is a 30 second video: Random Screen shots: <a class="lightbox" href="https://global.discourse-cdn.com/meta/original/4X/1/8/c/18c6b4b7561a708e826eead7ad442bdfa770af67.png" data-download-href="/uploads/short-url/3xbbseYL6ppNr01C5GLqheYSnmD.png?dl=1" title="The image displays a Unix-like system’s process list or task manager showing various running processes, with a focus on multiple instances of 'unicorn worker' processes, and provides specific details such as user ID, process ID, priority, CPU, memory usage, and estimated runtime. (Captioned by AI)" rel="noopener nofollow ugc">[The image displays a Unix-like system’s process list or task manager showing various running processes, with a focus on multiple instances of 'unicorn worker' processes, and provides specific details such as user ID, process ID, pri…

Yeah something is off: top -H -p PID_OF_UNICORN <a class="lightbox" href="https://global.discourse-cdn.com/meta/original/4X/4/5/9/45984d7071ef784855d4e9755d6365075782f7b0.png" data-download-href="/uploads/short-url/9VFfCTZqXLv5L2tvu6pocxFEaOY.png?dl=1" title="A screenshot showing a top command output indicating system resources and processes, with 367 threads, predominantly running a ruby or colourer-2480 process, and a mostly free but used RAM usage. (Captioned by AI)">[A screenshot showing a top command output indicating system resources and processes, with 367 threads, predominantly running a ruby or colourer-2480 process, and a mostly free but used RAM usage. (Captioned by AI)] I suspect you will see V8 Defaul…

Yes, it resolved the high CPU issue. My 1-minute and 5-minute load is about 1/3 of the previous values. That is with htop and netdata now running on the system. HTOP video Do Graph <a class="lightbox" href="https://global.discourse-cdn.com/meta/original/4X/f/5/7/f572a7a0a67d84a4eec26ab50e5c07acb41781d1.png" data-download-href="/uploads/short-url/z1kCShKrkm0yYTzHA4d9Py21mKZ.png?dl=1" title="The image shows two line graphs depicting CPU percentage and load (1/5/15) over various time intervals, with different lines representing different loads (0.100, 1.000, 15.000, and 50.150). (Captioned by AI)" rel="noopener nofollow ugc">[The image shows two line graphs depicting CPU percentage and load (1/5/15) over various time intervals, with d…

Sorry about this, the mini_racer upgrade has been a big adventure. Hopefully we get through it soon.

Thank you for the fast response to investigate. I am sure you had other things planned for the day versus a rollback. As a new Discourse user, 2 weeks since migration, the product has been great to work with.

Similar story here aswell. <a class="lightbox" href="https://global.discourse-cdn.com/meta/original/4X/7/9/0/7909cda076ed8c1eab27eb66486a635f8c237e57.jpeg" data-download-href="/uploads/short-url/hgKMbJLKh7yYtUl99rh9isuwU4v.jpeg?dl=1" title="The image displays a detailed graph with two charts: the upper chart is a colorful line graph showing CPU usage over time, highlighted with a significant peak on January 27th, marked with CPU usage of 2.03%, alongside the lower chart indicating system load in a line graph format, featuring negligible... (Captioned by AI)" rel="noopener nofollow ugc">[The image displays a detailed graph with two charts: the upper chart is a colorful line graph showing CPU usage over time, highlighted with a significant peak on January 27th, marked with CPU usage of 2.03%, alongside the lower chart indicating system load in a line gra…

Here is a performance review 18 hours after the rebuild. The load table says it all. Load Table: time Pre-fix post-fix 1 min 0.4 to 0.6 0.03 to 0.05 5 min 0.39 to 0.5 0.09 15 min 0.68 0.12 Legend: Red arrow - rebuilt the app Purple arrow - turned off netdata <a class="lightbox" href="https://global.discourse-cdn.com/meta/original/4X/e/4/d/e4de9efd4ea91c507161610c45cb7e3876a996a5.png" data-download-href="/uploads/short-url/wEFPfI7QFWdtd3jTtc2BMTicMPH.png?dl=1" title="The image shows two graphs: one with a red arrow indicating high CPU usage and another with a purple arrow showing spikes in load, both occurring at different times during the day. (Captioned by AI)" rel="noopener nofollow ugc">[The image shows two …

Note, closing the loop, the bug causing it was this: https://github.com/rubyjs/mini_racer/commit/edaa9e862abcd9945fbfcdd115d02dd7326569cf I updated the gem. One immediate advantage is that it appears this version of v8 uses slightly less memory which is nice.

I installed the latest release last night with the fix. CPU usage is back to historic levels. Thank you for all the great work.

3.4.0.beta4-dev(58f75ed205) 업그레이드 이후 CPU 사용량 증가

지원

sam (Sam Saffron) 2월 3, 2025, 6:18오전 5

OK this is reverted now,

https://github.com/discourse/discourse/pull/31119

Let me know if the commit restores performance.

High CPU usage (Ruby)

글		댓글	조회수
CPU usage increases steadily Support	14	293	3월 8, 2025
Higher idle process activity after upgrade Self-hosting	7	794	5월 25, 2020
High CPU usage (Ruby) Support server-resources	20	902	2월 3, 2025
Server Performance Issues Due to High CPU Usage Support	5	398	2월 23, 2025
Strange CPU usage since latest upgrade Self-hosting server-resources	14	1107	4월 11, 2019

3.4.0.beta4-dev(58f75ed205) 업그레이드 이후 CPU 사용량 증가

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