We have a problem of zabbix_agent reporting incorrect system load on CPUs with hyperthreading enabled.
Zabbix agent should look at the number of CPU cores, not at the number of virtual CPUs when computing load percentages. Right now on Hyperthreaded system 50% of shown CPU load actually means 100% of load - its not hard to get misleaded in server capacity by looking at the graph.
Clarification: if one virtual CPU is 100% occupied with the task and second virtual CPU located on the same CPU core does not perform any work, it does not mean that second CPU has 100% idle time, it is the same core which is at the moment loaded by 100%, but if you look at this if they were independent CPUs (which is what zabbix agent is doing) you would make false assumption that core is only 50% busy.
Zabbix agent should look at the number of CPU cores, not at the number of virtual CPUs when computing load percentages. Right now on Hyperthreaded system 50% of shown CPU load actually means 100% of load - its not hard to get misleaded in server capacity by looking at the graph.
Clarification: if one virtual CPU is 100% occupied with the task and second virtual CPU located on the same CPU core does not perform any work, it does not mean that second CPU has 100% idle time, it is the same core which is at the moment loaded by 100%, but if you look at this if they were independent CPUs (which is what zabbix agent is doing) you would make false assumption that core is only 50% busy.
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