Claudio Jeker <cje...@diehard.n-r-g.com> wrote: > On Wed, Oct 25, 2023 at 11:57:54AM +0200, Mike Fischer wrote: > > I have been observing occasional bouts of high load averages on several > > servers I administer and I am trying to find the cause. (I monitor these > > machines so that I can implement corrective measures in case of any > > malicious or abnormal activity. I think this is benign, but Iâd still > > like to find the cause.) > > > > Once the high load average starts, only a reboot seems to (temporarily) > > return the values to their normal levels. > > > > The actual CPU usage (as measured by vmstat) stays low even if the load > > average is elevated. > > > > The servers are VMs running on a VMWare host (ESXi). This was seen with > > OpenBSD 7.3 and 7.4 amd64. > > > > I can not determine anything inside the VM that causes this. There seems > > to be no correlation to pfstat(8) graphs, log entries, known events, or > > anything else I can determine. restarting all of the rc.d services never > > made any difference. > > > > Could this be caused by something on the VMWare host machine? (The host > > seems to be operating at limit regarding RAM for example. But the VM is > > only using the normal percentage of its allocated RAM â way below 100% > > and very constant usage, no swap.) > > > > How can I further debug this, keeping in mind that these are production > > machines and experimentation is limited to benign things that donât > > cause outages. > > > > What is high? A high CPU load for me is in the order of 70+. > Please remember the CPU load avarage is a horrible leftover from tenex > days. The system just counts how many processes are runnable but it is a > very bad indicator of actual CPU load.
Furthermore, every operating system counts this in a different way. You might think there is only one way to count it. Not at all.
