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hw:server:dellr720 [2025/12/10 09:15] – niziakhw:server:dellr720 [2025/12/11 08:52] (current) – niziak
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     * Enable checkmark in column ''Remote System Log''. NOTE: there are multiple pages of alerts. There is no need to click ''apply'' before changing page.     * Enable checkmark in column ''Remote System Log''. NOTE: there are multiple pages of alerts. There is no need to click ''apply'' before changing page.
     * test remote syslog using ''Test Event'' at bottom of page     * test remote syslog using ''Test Event'' at bottom of page
 +
 +
 +===== ENERGY_PERF_BIAS =====
 +
 +Despite of BIOS setting to ''performance'' kernel changes it during boot:
 +
 +<code bash>
 +kernel: ENERGY_PERF_BIAS: Set to 'normal', was 'performance'
 +</code>
 +
 +[[https://support.scc.suse.com/s/kb/Boot-log-displays-ENERGY-PERF-BIAS-Set-to-normal-was-performance?language=en_US]]:
 +
 +  The EPB MSR (ENERGY_PERF_BIAS Machine Specific Register) is a feature of some Intel CPUs.  It can be set to a value from 0-15 to tell the CPU (microcode) whether it should prefer performance (0) over powersave (15) power management.
 +  Intel has observed that on many systems after the hardware platform firmware (BIOS/UEFI) finishes initialization, the initial EPB value is 0 ('performance').  While on some systems this is intentional, on others it is due to the system firmware (UEFI/BIOS) not properly initializing the value of the EPB MSR.  Intel implemented a fix in the Linux kernel EPB initialization code to set the EPB to value of 6 ('normal') when the Linux kernel boots.  After the kernel finishes loading a proper EPB value can then be selected.  Unfortunately, this causes a bit of an inconvenience on systems where the system firmware deliberately set EPB to 0 as they will need to set the value back to 0 after Linux loads.  However, other systems (where the EPB value is 0 due to not having been properly initialized) have a higher power consumption than intended/desirable which can cause issues for systems operating from battery power (standby/ups power, or laptops).
 +
 +ENERGY_PERF_BIAS:
 +  * 0 - performance (140W)
 +  * 3 - (140W)
 +  * 4 - balance-performance (126W)
 +  * 6 - normal (126W)
 +  * 8 - balance-power
 +  * 15 - power (max power saving) (126W)
 + 
 +<code bash>
 +apt instal linux-cpupower
 +
 +# x86_energy_perf_policy
 +cpu0: EPB 6
 +cpu1: EPB 6
 +...
 +cpu30: EPB 6
 +cpu31: EPB 6
 +
 +# x86_energy_perf_policy balance-performance
 +</code>
 +
 +<code bash>
 +ipmitool sensor reading 'Pwr Consumption'
 +</code>