[pve-devel] Tickless kernel or not

[Thomas Lamprecht]

On 08/05/2015 04:40 PM, Dietmar Maurer wrote:
>> Redhat uses since RHEL7 a fully tickless kernel. Options:
>> CONFIG_NO_HZ=y
>> CONFIG_NO_HZ_FULL=y
>> CONFIG_RCU_FAST_NO_HZ=n
>> CONFIG_HZ_1000=y
>> CONFIG_HZ=1000
>>
>> PVE now uses:
>> CONFIG_NO_HZ=y
>> CONFIG_NO_HZ_IDLE=y
>> CONFIG_RCU_FAST_NO_HZ=y
>> CONFIG_HZ_250=y
>> CONFIG_HZ=250
> I just use the default config provided by RH/Ubuntu for that.
>
> Does it matter somehow?
The performance should go up, as not all cpus (cores) get constantly 
interrupted to do the kernel stuff, which isn't necessary, but only one. 
Nice to have, imo.