I discovered something that surprised me. On OpenVZ hardware node there is a big load, let's say the load is 210 (it have many CPU cores available but 210 is still high as for this server). But the the hardware node is working fine. According to the
top 75% of CPU is in idle state, performance is fine. But then I realized that one of many containers on this HW node have load of ~200, and when I am in that container (
vzctl enter container_id) there is a huge lag for everything that I do.
So, the container is using all of it's assigned resources, and that's why inside of it there is a lag while executing any command etc. But hardware node is fine, performance is ok, there is free memory, CPU power and disk usage is low, according to
iostat and tools like that and I can even feel it that the HW node is not overloaded, everything works smooth. But the load is ~210.
Someone told me that it's because OpenVZ hardware node is summing up loads from all containers instead of reporting it's own load. Is it true? If yes, then why is that? This is highly misleading. If no, then why HW node have so high load, but is not actually overloaded?