Troubleshooting • Raspberry pi 400 has high system load when ram and cpu are not at 100%

I'm running a lot of docker services on my raspberry pi, but I noticed that my pi's system load went over 40. I decided to investigate this issue and found out that both my cpu and ram usage are not at 100%. The cpu load was about 4% and the ram usage was about 3GB out of 4GB. I was suspecting that this might be caused by heavy usage of swap, but after looking at a few statistics I don't think swap is what's causing this. When the system load was really high, I opened `btop`. btop said that my external hdd was reading and writing at a combine speed of 20MB to 40MB per every 2 seconds. I also looked at grafana, and it said that my external hdd was reading at about 10MB/s and writing at about 100KB/s before it stopped recording data due to high system load. My swap file is located on my pi's microssd and not on the external hdd. Both btop and grafana said that the read and write speed on the microssd was around 0 to 100KB; however my swap is fully used at 100%. My btop and grafana was never able to see the the RAM usage going to anything close to 100%, it always hovers at around 75% to 80% (3GB/4GB) usage while the system load was really high.

The high system load usually happens when I started a new service or when my plex media server started transcoding videos. How I fixed this issue currently is to stop other services to lower the RAM usage even though the RAM usage never came close to 100%.

My current hypothesis: Either docker somehow limited the RAM usage of the services that I'm running or raspberry pi cannot fully utilize 100% of the ram for some reasons.

What is actually causing the high system load and how do I solve this issue?

Statistics: Posted by menhera — Sat Jun 22, 2024 8:05 pm — Replies 0 — Views 58

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