> > processor : 31 > > vendor_id : GenuineIntel > > cpu family : 6 > > model : 63 > > model name : Intel(R) Xeon(R) CPU E5-2630 v3 @ 2.40GHz > > stepping : 2 > > microcode : 0x46 > > cpu MHz : 1200.000 > > cache size : 20480 KB > > Your CPU is running at 1.2GHz although it is capable of 2.4GHz. This > looks like you have CPU frequency scaling activated. Investigate: > > grep -i cpu_freq /boot/config-5.15.28-rt35 node-0> grep -i cpu_freq /boot/config-5.15.28-rt35 CONFIG_ACPI_CPU_FREQ_PSS=y CONFIG_CPU_FREQ=y CONFIG_CPU_FREQ_GOV_ATTR_SET=y CONFIG_CPU_FREQ_GOV_COMMON=y CONFIG_CPU_FREQ_STAT=y CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE=y # CONFIG_CPU_FREQ_DEFAULT_GOV_POWERSAVE is not set # CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE is not set # CONFIG_CPU_FREQ_DEFAULT_GOV_SCHEDUTIL is not set CONFIG_CPU_FREQ_GOV_PERFORMANCE=y CONFIG_CPU_FREQ_GOV_POWERSAVE=y CONFIG_CPU_FREQ_GOV_USERSPACE=y CONFIG_CPU_FREQ_GOV_ONDEMAND=y CONFIG_CPU_FREQ_GOV_CONSERVATIVE=y CONFIG_CPU_FREQ_GOV_SCHEDUTIL=y AND: > > The configuration of your tick may also be interesting: > > grep -i hz /boot/config-5.15.28-rt35 > node-0> grep -i hz /boot/config-5.15.28-rt35 CONFIG_NO_HZ_COMMON=y # CONFIG_HZ_PERIODIC is not set CONFIG_NO_HZ_IDLE=y # CONFIG_NO_HZ_FULL is not set CONFIG_NO_HZ=y # CONFIG_HZ_100 is not set CONFIG_HZ_250=y # CONFIG_HZ_300 is not set # CONFIG_HZ_1000 is not set CONFIG_HZ=250 # CONFIG_MACHZ_WDT is not set > John Ogness It seems you are saying some of these settings, related to CPU freq scaling and "tick" settings may be the cause of my ~800 usec latencies I see. As I am seeking the "best possible that I can achieve" number I am willing to set the configs anyway needed. Any suggestions? Thanks. Gautam
